Method for increasing amino acid production in submerged corynebacteria culture

文档序号:1189042 发布日期:2020-09-22 浏览:11次 中文

阅读说明:本技术 在深层棒状杆菌培养中增加氨基酸产量的方法 (Method for increasing amino acid production in submerged corynebacteria culture ) 是由 L·G·布鲁德里克 P·G·卡伊米 T·M·格鲁伯尔 B·G·勒菲弗 Y·任 于 2018-11-20 设计创作,主要内容包括:描述了用于在深层棒状杆菌培养中提高氨基酸谷氨酸和赖氨酸产量的方法,所述方法包括向深层棒状杆菌培养中添加用过的木霉发酵液的非酶级分,其中与在没有用过的木霉发酵液的非酶级分的情况下在相同的深层培养中生长的棒状杆菌相比,在用过的木霉发酵液的非酶级分存在下生长的棒状杆菌产生的小分子量增加,其中氨基酸谷氨酸和赖氨酸产量的增加不是由于用过的木霉发酵液中的酶活性。(A method for increasing the production of the amino acids glutamic acid and lysine in a C.deep culture is described, the method comprising adding a non-enzymatic fraction of a used Trichoderma fermentation broth to the C.deep culture, wherein the increase in production of the amino acids glutamic acid and lysine is not due to enzymatic activity in the used Trichoderma fermentation broth, produces an increase in small molecular weight compared to a C.corynebacterium grown in the same submerged culture without the non-enzymatic fraction of the used Trichoderma fermentation broth, wherein the increase in production of the amino acids glutamic acid and lysine is due to the same enzyme activity in the used Trichoderma fermentation broth.)

1. A method for increasing small molecule production in Corynebacterium submerged (Corynebacterium) culture, comprising adding a non-enzymatic fraction of a used Trichoderma (Trichoderma) fermentation broth to Corynebacterium submerged culture, wherein the small molecule production by the Corynebacterium grown in the presence of the non-enzymatic fraction of the used Trichoderma fermentation broth is increased as compared to a Corynebacterium grown in the same submerged culture in the absence of the non-enzymatic fraction of the used Trichoderma fermentation broth, wherein the increase in small molecule production is not due to enzymatic activity in the used Trichoderma fermentation broth.

2. The method of claim 1, wherein the non-enzymatic fraction of the used trichoderma fermentation broth is produced by filtering a complete or fractionated used trichoderma fermentation broth.

3. The method of claim 1, wherein the non-enzymatic fraction of the used trichoderma fermentation broth is produced by heat treating a whole or fractionated used trichoderma fermentation broth.

4. The method of claim 1, wherein the non-enzymatic fraction of the used trichoderma fermentation broth used to increase small molecule production is a component of the whole or fractionated used trichoderma fermentation broth added to the corynebacterium submerged culture.

5. The method of any one of the preceding claims, wherein the non-enzymatic fraction of the used trichoderma fermentation broth is a byproduct of a recombinase-producing fermentation.

6. The method of claim 5, wherein the non-enzymatic fraction of the Trichoderma fermentation broth used to increase small molecule production further comprises the recombinant enzyme.

7. The method of claim 5, wherein the recombinant enzyme is removed from a non-enzymatic fraction of the Trichoderma fermentation broth used to increase small molecule production.

8. The method of any one of claims 5-7, wherein the recombinase is a carbohydrate processing enzyme.

9. The method according to any of the preceding claims, wherein at least a part of the used fermentation broth is added when the corynebacterium culture is inoculated.

10. The method of any one of the preceding claims, wherein the spent fermentation broth is harvested from the trichoderma growth culture at least 29 hours after inoculation with trichoderma broth.

11. The method of any one of the preceding claims, wherein the spent fermentation broth is harvested from a trichoderma growth culture prior to expressing a protein of interest in the broth.

12. The method of any one of the preceding claims, wherein the small molecule is an amino acid.

13. The method of claim 12, wherein the amino acid is glutamic acid or lysine.

14. The method according to any of the preceding claims, wherein the increase in production of small molecules is not the result of an increase in cell mass in the culture of corynebacteria.

15. A small molecule produced in a culture of corynebacterium deep layer produced by the method of any one of claims 1-14.

16. Use of a non-enzymatic fraction of a used trichoderma fermentation broth for increasing the amount of small molecules produced in corynebacterium submerged culture.

17. Use of a non-enzymatic fraction of a used trichoderma fermentation broth according to claim 16 in combination with the features according to any one of claims 1-14.

Technical Field

The present method relates to increasing the yield of small molecules in submerged corynebacteria cultures by supplementing the Corynebacterium (Corynebacterium) growth medium with a non-enzymatic fraction of spent Trichoderma (Trichoderma) fermentation broth.

Background

Corynebacteria are gram-positive aerobic bacilli that include members that are useful in industrial applications as well as human pathogens. Nonpathogenic species of corynebacteria are used for the production of amino acids, nucleotides, steroids, bacteriocins and enzymes. The most well-known species is corynebacterium glutamicum (c.glutamicum), which produces glutamic acid sold as monosodium glutamate in the food industry. Genetically engineered C.glutamicum produces lysine. Corynebacteria are usually grown in submerged culture using glucose, fructose or glucose plus fructose and sucrose as the main carbon sources.

Trichoderma is a filamentous fungus (filmentous fungi) present in soil. Many species are characterized as opportunistic, non-toxic plant symbionts. Trichoderma produces a variety of enzymes, including cellulases and hemicellulases. Trichoderma is also engineered to produce and secrete recombinant enzymes such as catalase, glucoamylase, laccase, and the like. Trichoderma is very productive and titers of more than 100 g recombinant enzyme per liter of submerged culture are not uncommon. Some trichoderma enzyme products are sold as complete broth products, typically comprising killed cells. Other trichoderma enzyme products are sold in purified form, in which case the spent trichoderma growth medium will be discarded.

Disclosure of Invention

The present method relates to increasing the production of small molecules in submerged corynebacteria culture by supplementing the corynebacteria growth medium with a non-enzymatic fraction of spent trichoderma fermentation broth. Aspects and embodiments of the method are described in the following independently numbered paragraphs.

1. In one aspect, there is provided a method for increasing small molecule production in corynebacterium submerged culture, the method comprising adding a non-enzyme fraction of a used trichoderma fermentation broth to corynebacterium submerged culture, wherein corynebacterium grown in the presence of the non-enzyme fraction of the used trichoderma fermentation broth produces an increase in small molecule weight compared to corynebacterium grown in the same submerged culture without the non-enzyme fraction of the used trichoderma fermentation broth, wherein the increase in small molecule production is not due to enzyme activity in the used trichoderma fermentation broth.

2. In some embodiments of the method of paragraph 1, the non-enzymatic fraction of the used trichoderma fermentation broth is produced by filtering a whole or fractionated used trichoderma fermentation broth.

3. In some embodiments of the method of paragraph 1, the non-enzymatic fraction of the used trichoderma fermentation broth is produced by heat treating a whole or fractionated used trichoderma fermentation broth.

4. In some embodiments of the method of paragraph 1, the non-enzymatic fraction of the used trichoderma fermentation broth used to increase small molecule production is a component of the whole or fractionated used trichoderma fermentation broth added to the corynebacterium submerged culture.

5. In some embodiments of the methods of any of the preceding paragraphs, the non-enzymatic fraction of the used trichoderma fermentation broth is a byproduct of a fermentation that produces the recombinant enzyme.

6. In some embodiments of the method of paragraph 5, the non-enzymatic fraction of the trichoderma fermentation broth used to increase small molecule production further comprises the recombinant enzyme.

7. In some embodiments of the method of paragraph 5, the recombinant enzyme is removed from a non-enzymatic fraction of the trichoderma fermentation broth used to increase small molecule production.

8. In some embodiments of the methods of any of paragraphs 5-7, the recombinase is a carbohydrate processing enzyme.

9. In some embodiments of the methods of any of the preceding paragraphs, at least a portion of the spent fermentation broth is added when the corynebacterium culture is inoculated.

10. In some embodiments of the methods of any of the preceding paragraphs, the spent fermentation broth is harvested from the trichoderma growth culture at least 29 hours after inoculation with trichoderma broth.

11. In some embodiments of the methods of any of the preceding paragraphs, the spent fermentation broth is harvested from a trichoderma growth culture prior to expressing the protein of interest in the broth.

12. In some embodiments of the methods of any of the preceding paragraphs, the small molecule is an amino acid.

13. In some embodiments of the method of paragraph 12, the amino acid is glutamic acid or lysine.

14. In some embodiments of the methods of any of the preceding paragraphs, the increase in production of the small molecule is not a result of an increase in cell mass in the culture of corynebacteria.

15. In another aspect, there is provided a small molecule produced by the method of any one of paragraphs 1-14 in culture with corynebacterium deep.

16. In another aspect, there is provided the use of a non-enzymatic fraction of a used trichoderma fermentation broth for increasing the amount of small molecules produced in corynebacterium submerged culture.

17. In some embodiments, the use of a non-enzymatic fraction of a used trichoderma fermentation broth as described in paragraph 16 is combined with the features described in any one of paragraphs 1 to 14.

These and other aspects and embodiments of the method of the invention will be apparent from the description, including the drawings.

Drawings

FIG. 1 is a graph showing the glucose consumption (g/L) and glutamic acid production (g/L) as a function of time (hours) in a coryneform bacterium culture to which a used Trichoderma fermentation broth was added.

FIG. 2 is a graph showing the total secreted protein yield (g/L) and the dry cell weight (g/kg) in Trichoderma culture from which used Trichoderma fermentation broth was periodically sampled.

FIG. 3 is a graph showing the effect of spent Trichoderma broth taken from Trichoderma culture at various time points (hours) on glutamic acid production (g/L) in Corynebacterium culture.

Detailed Description

I. Introduction to the design reside in

The present method relates to increasing the production of small molecules in submerged corynebacteria culture by supplementing the corynebacteria growth medium with a non-enzymatic fraction of spent trichoderma fermentation broth.

Definitions and abbreviations II

Before describing the method in detail, the following terms are defined for clarity. Undefined terms should be accorded the conventional meaning used in the relevant art.

As used herein, "submerged culture" refers to a method for growing a culture of microorganisms in which the microorganisms are incubated in a liquid medium that is subjected to continuous vigorous agitation.

As used herein, a "fermenting organism" is a microorganism that is capable of producing a product of interest (such as an amino acid or protein) when grown in submerged culture.

As used herein, "spent broth" refers to a submerged culture growth medium in which microorganisms have been grown. The spent broth contains the compound secreted into the culture medium. "fully spent" broth also includes microorganisms (cells) grown in culture. The "fractionated used broth" has been treated in a manner to remove at least some of the components of the used broth.

As used herein, the "non-enzyme fraction" of the used broth is substantially free of enzyme protein or substantially free of enzyme activity, even though denatured enzyme protein may be present.

As used herein, a "small molecule" is a non-polymeric, low molecular weight (<900Da) organic compound.

As used herein, "trichoderma" is a genus of organisms with the following lineages by 2017 according to the national center for biotechnology information (NCBI, Bethesda, maryland, USA (NCBI, Bethesda MD, USA): a eukaryote; a posterior flagellar organism; fungi; binuclear bacterial subclass (Dikarya); ascomycota (Ascomycota); yeast (saccharomyces); phylum subphylum (Pezizomycotina); class hammock (leotiomyceta); chaetomium super class (sordariomyceta); coprophila (Sordariomycetes); hypocrea (Hypocremycetidae); hypocrea (Hypocrea); hypocreaceae (Hypocrea).

As used herein, "corynebacteria" are genera of organisms with the following lineages by 2017 according to NCBI: bacteria; terrestrial bacteria (Terrabacteria group); actinomycetea (actinobacilla); actinomycetes (actinobacilla); corynebacteriales (Corynebacteriales); corynebacteriaceae (Corynebacteriaceae).

As used herein, the singular articles "a" and "an" and "the" encompass a plurality of the referents unless the context clearly dictates otherwise. All references cited herein are hereby incorporated by reference in their entirety.

Unless otherwise indicated, the following abbreviations/acronyms have the following meanings:

da Dalton

w/v weight/volume

w/w weight/weight

v/v volume/volume

DEG C

g or gm gram

Microgram of μ g

mg of

kg kilogram

μ L and μ L microliter

mL and mL

mm

Micron diameter of

mol mole of

mmol millimole

M moles of

mM millimolar

Micromolar of μ M

nm nanometer

ppm parts per million parts

hr or hrs

RPM RPM

Standard liter per minute of SLPM

Spent Trichoderma broth

Trichoderma is widely used for the production and secretion of recombinant enzymes on an industrial scale (see for example,

Figure BDA0002625042890000061

s, and(1995) Current Opinion in Biotechnology [ New concept of Biotechnology]534-37 parts of; ahamed, a, and Vermette, p. (2009) bioreresource Technology]5979-87 parts by weight; and Helena Nevalainen, H and Petersonl, R. (2014) Front Microbiol [ microbiology Front].5:75). Strains, media components and culture conditions are well known.

The present method relates to the use of a fully or fractionated spent trichoderma fermentation broth (necessarily comprising the non-enzymatic fraction of the spent broth) to increase the amount of small molecules produced by corynebacteria grown in submerged culture.

In some embodiments, only the non-enzymatic fraction of the used trichoderma broth is added to the corynebacterium culture. This fraction may be substantially free of enzyme, meaning that no protein with enzymatic activity is present in the broth, or may be substantially free of active enzyme, meaning that the enzymatic activity in the broth has been disrupted by physical or chemical treatment of the broth.

The enzyme activity can be eliminated by filtering the used Trichoderma broth to separate components having a beneficial effect on the culture of Corynebacterium from the protein having the enzyme activity. Such filtration may encompass filtration to remove proteins having a molecular weight greater than about 30 KDa.

The enzymatic activity can alternatively or additionally be disrupted by heating the used trichoderma broth to a temperature above about 70 ℃, above about 75 ℃, above about 80 ℃, above about 85 ℃, above about 90 ℃ or even above about 95 ℃ for a time sufficient to denature the enzyme (e.g., at least about 10 minutes, at least about 15 minutes, at least about 20 minutes, at least about 30 minutes or at least about 40 minutes or more).

The enzymatic activity may alternatively or additionally be disrupted by incubating the spent trichoderma broth with a small molecule protease inhibitor, or other small molecule that inhibits the activity of a particular class of enzymes.

The enzymatic activity may alternatively or additionally be disrupted by incubating the used trichoderma broth with an active protease enzyme (which may be exogenous to the used trichoderma broth) such that proteins present in the used trichoderma broth are digested and substantially no enzymatic activity remains in the used trichoderma broth.

The enzymatic activity may alternatively or additionally be disrupted by subjecting the used trichoderma broth to chromatography conventionally used to separate proteins from other components in the used trichoderma broth, the separated proteins being the source of the enzymatic activity in the used trichoderma broth.

The enzyme activity may alternatively or additionally be disrupted by selecting a particular strain of trichoderma or genetically modifying trichoderma to eliminate or reduce expression or secretion of the enzyme in the spent trichoderma broth to reduce or eliminate expression and/or secretion of the native or non-native (i.e. recombinant) protein (which may be an enzyme).

The non-enzymatic fraction of the used trichoderma broth can be included as a proprietary product in the whole or other fractionated used trichoderma broth. Alternatively, the non-enzymatic fraction of the used trichoderma broth may be provided as a dedicated fractionation product of the used trichoderma broth.

In some embodiments, the non-enzymatic fraction of the spent trichoderma broth alone further comprises one or more proteins of interest, for example, carbohydrate processing enzymes and other commercially relevant polypeptides, including but not limited to dehydrogenases, transketolases, phosphoketolases, transaldolases, epimerases, phytases, xylanases, beta-glucanases, phosphatases, proteases, alpha-amylases, beta-amylases, glucoamylases, pullulanases, isoamylases, cellulases, trehalases, lipases, pectinases, polyesterases, cutinases, oxidases, transferases, reductases, hemicellulases, mannanases, esterases, isomerases, pectinases, lactases, peroxidases, and laccases.

In other embodiments, only the non-enzymatic fraction of the used trichoderma broth specifically excludes any particular protein of interest, including the enzyme protein of interest, in particular the recombinant protein of interest.

In some embodiments, the used trichoderma broth or fraction thereof is formulated, for example, for storage stability or ease of handling. Formulation components include, but are not limited to, glycerin, sorbitol, salts, polymers, preservatives, and the like.

Cultivation of deep coryneform bacteria

As described herein, the present methods involve adding spent Trichoderma broth to a small molecule producing culture of Corynebacterium. Corynebacteria naturally produce large amounts of glutamate and can be readily genetically modified to produce other products, including but not limited to lysine (see, e.g., de Graaf, a.a. et al (2001) Adv Biochem EngBiotechnol [ biochemical engineering-biotechnological progress ].73:9-29 and wendis, v.f. et al (2016) World JMicrobiol Biotechnol [ journal of microbiology and biotechnology ].32: 105). Many strains of corynebacteria are commercially available, the most common being derivatives of corynebacterium glutamicum. The complete genomic sequence of C.glutamicum S9114 is known.

For the production of commercially valuable products, conditions for growing corynebacteria in submerged culture are well known, for example, Kusumoto, I. (2001) J.Nutr. [ J.Nutr ]131: 2552S-55S; hermann, T. (2003) JBiotechnol. [ J. Biotechnology ]104: 155-; zhiting Luo, Z. et al (2016) Biotechnology for Biofuels biotech 9: 134; and Zahoora, a. et al (2012) csbj.3: e 201210004.

The corynebacterium growth medium generally includes a major carbon source such as glucose, fructose, or sucrose, although carbon sources such as cane molasses, xylose, agricultural industrial waste, rapeseed meal, bean dregs, corn cob fiber, and glycerol are also used. Yeast extract is a suitable nitrogen source, but ammonium sulfate and ammonium chloride are more cost effective. Inorganic salts (and especially manganese) affect the productivity of corynebacteria.

In some embodiments, the amount of the whole or fractionated used trichoderma broth as a percentage of the total amount of corynebacterium growth medium is at least 0.01%, at least 0.02%, at least 0.03%, at least 0.04%, at least 0.05%, at least 0.06%, at least 0.07%, at least 0.08%, at least 0.09%, at least 0.10%, at least 0.12%, at least 0.14%, at least 0.16%, at least 0.18%, at least 0.2%, at least 0.3%, at least 0.4%, at least 0.5%, at least 0.6%, at least 0.7%, at least 0.8%, at least 0.9%, at least 1%, at least 2%, at least 5% or more (v/v).

Preferably, the used trichoderma broth, either completely or fractionated, is added when the corynebacterium culture is inoculated. However, in fed-batch fermentation processes, it may be necessary to stagger the addition of used trichoderma broth. For example, a 50% dose of trichoderma broth may be added when inoculating a corynebacterium culture, then 25% at about 10 hours after inoculation, and the remaining 25% at about 16 hours after inoculation.

These and other aspects and embodiments of the method of the invention will be apparent to the skilled person in view of the present description. The following examples are intended to further illustrate but not limit the process.

Examples of the invention

Example 1 organisms, culture media and spent Broth

Corynebacterium glutamicum strains ATCC13032 and ATCC15990 from the American type culture Collection (Manassas, Va.) were used for all L-glutamic acid experiments.

Corynebacterium glutamicum strain ATCC 21513 from the American type culture Collection (Manassas, Va.) was used for all L-lysine production experiments.

Trichoderma reesei strain Morph, described in PCT application No. WO 05/001036, was used for all experiments.

The fully spent broth of Trichoderma reesei contains (w/w) water (80% -98%) and (%), pH 4.5-5.0.

The prepared fully spent broth of trichoderma reesei contains (w/w) water (33% -45%), glycerol (47% -53%) and sodium chloride (3% -4%) at a pH of 4.5-5.0.

CGXII medium containing (per liter) 50g glucose, 20g ammonium sulfate, 5g urea, 1g potassium phosphate (monovalent), 1g potassium phosphate (divalent), 0.25g magnesium sulfate, 42g 3- (N-morpholino) propanesulfonic acid (MOPS), 10. mu.g calcium chloride, 35. mu.g 3, 4-dihydroxybenzoic acid, trace elements (1mg FeSO)4、1mg MnSO4、0.1mg ZnSO4、0.02mg CuSO4And 0.002mg NiCl2) 1.0. mu.g biotin, adjusted to pH 7.0 using sodium hydroxide.

Glutamic acid fed-batch fermentation medium contained (per liter) 15g Sigma corn steep liquor solids, 10g (NH)4)2PO4、2.0g K2HPO40.5mL Sigma 204 antifoam, 50mL of 100 Xmicroelement solution (containing 80g of MGSO)4·7H2O、2.2g FeSO4·7H2O and 2.2g MnSO4·H2O) and 5mL of a 1000 Xvitamin solution (containing 0.2g vitamin B1 thiamine), 545g 55% w/w glucose.

Lysine seed shake flask medium contained 5.0g Difco yeast extract, 10g Difco selection soytone, 10g NaCl and 10.0g glucose per liter.

The lysine fermentation medium contained 52.5g of soybean meal hydrolysate, 2.4g of molasses, 12.4g (NH) per liter4)2SO40.7g citric acid monohydrate, 2.2g 85% H3PO4、1.24g MgSO4·7H2O、1.24g MnSO4·H2O、0.002g ZnSO4·7H2O、0.038g FeSO4·7H2O, 0.55g L-threonine, 0.60g L-methionine, 0.0006g biotin, 0.00024g thiamine hydrochloride, 0.5ml Sigma 204 antifoam, in an initial bolus batch of 545g of 55 wt% 95DE (Cargill 95DE dextrose).

The lysine carbon source feed contained: 55% by weight 95DE (Cargill 95DE dextrose)

EXAMPLE 2 stimulation of glutamic acid production by Corynebacterium

The prepared fully spent broth of trichoderma reesei was added to a shake flask assay containing one of two different corynebacterium glutamicum strains to determine the effect on glutamate titre and shorten fermentation time. Corynebacterium glutamicum strains ATCC13032 and ATCC15990 were grown from glycerol stocks on LB agar plates by incubation at 30 ℃. Cells were transferred to liquid CGXII medium and incubated overnight at 30 ℃ with shaking (250 RPM). The cells were transferred a second time and grown overnight in CGXII medium and then used in production shake flasks.

Then, ATCC13032 Corynebacterium cells were inoculated into fresh CGXII medium at an initial OD of 0.025-0.1(600nm) and used Trichoderma broth (or water as a negative control) was added at different concentrations/doses. The 1X dose represents a 1250-fold dilution of the used Trichoderma broth in the Corynebacterium culture medium (0.08% of the total volume). The 5X dose represents a 625-fold dilution (i.e., 0.4% of the total volume), while the 10X dose represents a 125-fold dilution (0.8% of the total volume).

The shake flasks were incubated at 30 ℃ for about 48 hours with shaking (250 RPM). At the end of this incubation, the final cell mass was determined using absorbance at 600nm and the glutamic acid concentration was determined using HPLC analysis (pre-column derivatization using o-phthaldialdehyde, C18 column and methanol/acetonitrile gradient as mobile phase). Each concentration was tested in duplicate and the average results are listed in table 1.

TABLE 1 Effect of used Trichoderma broth on ATCC13032 cell quality and glutamic acid production

Control 1X 5X 10X
OD(A600nm) 16.85 18.20 22.65 25.80
% increase over control - 7% 26% 35%
Glutamic acid (g/L) 5.77 6.73 10.02 10.18
% increase over control - 14% 42% 43%

The results show that in the presence of spent trichoderma broth, the dose-dependent response of cell mass and glutamic acid production increases up to the saturation point (at which no further increase is possible), probably due to complete conversion of the available sugars.

The experiment was repeated using ATCC15990 strain in Corynebacterium CGXII medium using 10X dose (0.8% by volume) of used Trichoderma broth. The results are shown in table 2.

TABLE 2 Effect of used Trichoderma broth on ATCC15990 cell quality and glutamic acid production

Control 10X
OD(A600nm) 15.6 25.45
% increase over control - 39%
Glutamic acid (g/L) 6.83 10.1
% increase over control - 32%

Additional samples of used trichoderma broth were tested in duplicate to determine if the positive effect on glutamate production was an isolated phenomenon. A total of five used complete trichoderma broths (a-E) were tested at 10X dose using ATCC13032 strain as described above. The results show a consistent increase in glutamate production in the presence of either spent trichoderma broth tested (table 3).

TABLE 3 Effect of different used Trichoderma broth on cell quality and glutamic acid production

The effect of the culture medium and the formulation components related to the used trichoderma broth was excluded by adding fresh (i.e., non-inoculated) trichoderma culture medium, citric acid or glycerol to the corynebacterium culture in the same manner as the used trichoderma broth was added. No increase in cell mass or glutamate was detected (data not shown).

EXAMPLE 3 time course Corynebacterium cultivation experiment

Glucose consumption and glutamate production over time were analyzed in similar shake flask assays using 1X and 10X doses of formulated spent trichoderma broth. Samples of the Corynebacterium culture (ATCC13032 strain) were periodically taken over a period of about 70 hours. The results are shown in FIG. 1. The results show that addition of spent trichoderma broth increases glutamic acid production, which persists throughout the process.

Example 4 treatment of spent Trichoderma broth to eliminate enzymatic Activity

The spent Trichoderma broth contains a number of enzymes that may affect the growth of Corynebacterium. To test whether any of these enzymes could cause the effects observed in the foregoing examples, spent trichoderma broth was treated to inactivate the enzymes. Specifically, the spent trichoderma broth was centrifuged at 14K × g for 20 minutes, and the supernatant was collected. The supernatant was filtered through a 30kDa membrane (labeled "< 30K") and the permeate was collected for testing in corynebacteria cultures. A portion of the filtered sample was further heat treated at 90 ℃ for 30 minutes (labeled "heat"). When viewed by SDS-PAGE analysis, the treated samples were found to contain much lower total protein levels compared to the crude used Trichoderma broth. The activity of enzymes known to be overexpressed in crude spent trichoderma broth was determined in the treated spent trichoderma broth, and no activity was detected (data not shown).

TABLE 4 influence of treated spent Trichoderma broth on cell quality and glutamic acid production

Despite the lack of enzymatic activity and almost complete absence of protein, the treated spent trichoderma broth still improved glutamate production at 10X dose as demonstrated by the shake flask test summarized in table 4.

EXAMPLE 5 time course Trichoderma cultivation experiment

In order to determine when non-enzymatic components capable of increasing the glutamic acid production of corynebacteria appeared in the spent trichoderma broth, time course experiments involving trichoderma culture were performed. Trichoderma was grown in culture for up to 213 hours, and used broth samples were taken periodically. The dry cell weight ("DCW") and secreted protein levels in the cultures are shown in figure 2. Samples were filtered through 0.2 μ M filters at each time point to remove cells.

Samples of used trichoderma broth taken at different time points were then added to the corynebacterium shake flask culture at a 10X dose and the amount of glutamic acid produced was measured as described above. The results are shown in fig. 3. The results showed that the non-enzymatic components present in the used trichoderma broth, which increase the glutamic acid production of corynebacteria, were not present at the 0.3 hour time point of the growth of the trichoderma culture. However, the components are present at the earliest stages of the fermentation time, at least as long as 29 hours, and remain throughout the fermentation. Notably, at the 29 hour time point, the secreted protein levels were very low. This particular Trichoderma organism also overexpressed a different protein than that used in the previous example, further emphasizing that the observed effect on Corynebacterium culture was not dependent on the genes of interest that Trichoderma might express.

EXAMPLE 6 stimulation of glutamic acid production in fed-batch fermentation

The prepared fully used broth or processed broth of trichoderma reesei was added to a fermentor containing corynebacterium glutamicum to determine the effect on glutamate production rate, titer and yield. Corynebacterium glutamicum strain ATCC13032 was grown from glycerol stock in glutamic acid seed shake flask medium and incubated overnight at 30 ℃ with shaking (200 RPM). Cells were transferred to seed shake flasks and grown overnight in the same medium before being used in the production fermentor. An overnight seed culture was used to inoculate the glutamic acid fermentation medium with an initial OD of 0.1(600 nm).

The fermentation was carried out at 30 ℃ with mixing to maintain 30% dissolved oxygen controlled by stirring at a minimum set point of 300rpm to a maximum of 1200rpm, then pressurized to a maximum of 1.5 bar and aerated to a maximum of 10.0 (normal liters per minute) during the fermentation.

Starting at 14 hours of fermentation time, a carbon source feed (containing 55 wt% 95DE (Cargill 95DE dextrose)) was used at a constant feed rate of 0.75 g/min. Either a 1X or 5X dose of fully spent trichoderma broth or a 1X dose of heat-treated spent broth (or no broth added as a control) was added to the corynebacterium fermentation. Half of the total dose of trichoderma broth was added at the time of inoculation with corynebacteria, 25% was added 10 hours after inoculation, and the remaining 25% was added 16 hours after inoculation.

At the end of this incubation, the final glutamic acid concentration was determined using HPLC analysis (pre-column derivatization using o-phthalaldehyde, C18 column and methanol/acetonitrile gradient as mobile phase) using a 1200 series agilent scientific fluorescence detector. The results in table X summarize the results for the percentage increase in the rate, titer and yield of glutamic acid at the end of the fermentation compared to the untreated control tank. The results show that glutamate titers (reported as acids) were lower in the control fermenters compared to the test tanks. The glutamic acid level was higher in fermenters containing 1 or 5X dose of fully used trichoderma broth or 1X dose of heat treated fully used trichoderma broth compared to the control. The results also show an increase in the rate and yield of glutamic acid at the end of the fermentation compared to the untreated control tank.

TABLE 5 Effect of treated spent Trichoderma broth in fed-batch fermentation on glutamic acid production

Fermentation parameters Glutamic acid titer Volume rate of glutamic acid Glutamic acid yield
Control 0.0 0.0 0.0
1X dose 9.5 8.6 5.2
1X Heat treatment dosage 4.6 4.5 5.9
5X dose 12.9 11.9 6.8

EXAMPLE 7 stimulation of lysine production by Corynebacterium

The prepared broth completely used by Trichoderma or the heat-treated broth was added to a fermenter containing Corynebacterium glutamicum strain ATCC 21513 to determine the effect on L-lysine titer and shorten fermentation time. Corynebacterium glutamicum strain ATCC 21513 was grown from glycerol stock medium and incubated overnight in lysine seed medium at 30 ℃ with shaking (250 RPM). Cells were transferred to larger seed shake flasks and grown overnight in liquid seed shake flask medium before being used in the production fermentor. The cells were then inoculated into fresh lysine fermentation medium at an initial OD of 0.1(600nm) and used trichoderma broth or processed broth was added at different concentrations/doses. The 1X dose represents 0.10 wt% of the fermentation medium.

Fermentation was carried out at 30 ℃ with mixing to maintain 30% dissolved oxygen controlled by stirring at maximum 1200rpm, then pressurized to maximum 1.5 bar and aerated to maximum 10.00SLPM during fermentation. Starting at 14 hours of fermentation time 14, a lysine carbon source feed (containing 55 wt% 95DE (Cargill 95DE dextrose)) was used at a constant feed rate of 0.75 g/min. Either a 1X or 5X dose of fully spent trichoderma broth or a 1X dose of heat-treated spent broth (or no broth added as a control) was added to the corynebacterium fermentation. Half of the total dose of trichoderma broth was added at the time of inoculation with corynebacteria, 25% was added 10 hours after inoculation, and the remaining 25% was added 16 hours after inoculation.

At the end of this incubation, the final L-lysine concentration was determined using HPLC analysis (pre-column derivatization using o-phthalaldehyde, C18 column and methanol/acetonitrile gradient as mobile phase) using a 1200 series agilent scientific fluorescence detector.

The results in table 6 further summarize the results of the percentage increase in the rate, titer and yield of fermented lysine at the end of the run compared to the control. Peak lysine titers were observed at the end of the run. The results show a significant increase in lysine yield in the presence of spent trichoderma broth.

TABLE 6 influence of treated spent Trichoderma broth on lysine production

Figure BDA0002625042890000151

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