• The Korean Journal of Food And Nutrition
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• v.1 no.2
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• pp.37-42
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• 1988

In attempts to obtain IMP Producting strains, Brevibacterium ammoniagenes ATCC 6872 was treated wilts N.1.6. Adenine-guanine requiring mutants were obtained from Brevibacterium ammoniagenes ATCC 6872, and then a strain of them was selected for production of IMP and named Brevibacterium ammoniagenes No.9(ade', gu'). The production of IMP by Brevibacterium ammoniagenes nuts No.9 was about 3mg/ml for 4 day of culture. The optimal concentration of adenine and guanine was 150mg/mg.

• Microbiology and Biotechnology Letters
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• v.15 no.2
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• pp.104-111
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• 1987

As a trial method of breeding L-lysine producing strains, the intraspecific protoplast fusion bet-ween Brevibacterium flavum ATCC 21528R and Brevibacterium flavum ATCC 21529S and the intergeneric protoplast fusion between Brevibacterium flavum ATCC 21528R and Corynebacterium glutamicum ATCC 13058S were performed. The optimum conditions for protoplast formation of these strains were examined and the effect of plasma expander on regeneration and/or fusion was also observed. Both fusants No. CH23 and No. CH4l showed higher productivity of L-lysine than those of parental cells under the optimum cultural conditions at a rate of 21％ and 8.9％, respectively. And, activity of several enzymes in L-lysine biosynthetic pathway including aspartokinase, a rate-limiting enzyme, was determined. Besides, metabolic control mechanism of L-lysine biosynthesis in fusant No. CH23 and in No. CH41 was investigated to compare with that of parental strains.

• Korean Journal of Microbiology
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• v.23 no.3
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• pp.190-196
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• 1985

For frequency improvement of protoplast fusion in Brevibacterium flavum, Brevibacterium lactofermentum lactofermentum and Corynebacterium glutamicum, the effect of plasma expanders on fusion and cell wall regeneration, compatison between direct and two-step selection method, tendency of fusion frequency according to pH of fusion fluid and polyethylene glycol concentration were examined. By addition of 3% polyvinyl pyrrolidone to cell wall regeneration medium, regeneration frequencies were expressed 23 (Brevibacterium lactofermentum), 10.4 (Brevibacterium flavum) and 2.7 (Corynebacterium glutamicum) times higher than those of none polyvinyl pyrrolidone medium respectively.

• Microbiology and Biotechnology Letters
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• v.13 no.3
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• pp.279-283
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• 1985

As a method of breeding L-lysine producing strains, the intergeneric protoplast fusion between Brevibacterium flavum and Corynebacterium glutamicum was performed. As a results, Brevibacterium flavum ATCC 21528 R showed 99％ of protoplast formation and 10％ of regeneration frequencies when treated with 400$\mu\textrm{g}$/$m\ell$ of lysozyme for 12hrs. In Corynebacterium glutamicum ATCC 21514 S, 99％ and 12％ were obtained by treatment of 300$\mu\textrm{g}$/$m\ell$ lysozyme for 12 hrs. In intergeneric protoplast fusion between Brevibacterium flavum ATCC 21528 R and Corynebacterium glutamicum ATCC 21831 S, 1.0$\times$10$^{-6}$ of recombinant frequency per regenerable cells was observed by use of PEG 6000, 30％(w/v). Among the strains obtained KR$_{43}$ strain showed 12％ higher productivity of L-lysine than the parental cell. Then, the activity of aspartokinase of KR$_{43}$ was about 13％ higher than the parental cell.

• Microbiology and Biotechnology Letters
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• v.17 no.5
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• pp.429-435
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• 1989

A bacterial strain of Brevibaterium sp. CH1 was isolated and used to produce an enzyme (nitrile hydratase) necessary for earring out the bioconversion of acrylonitrile to acrylamide. The culture and reaction conditions, and medium optimization were studied for the strain. The conversion yield was nearly 100％ with a trace amount of acrylic acid produced. The strain showed strong activity of nitrile hydratase toward acrylonitrile and extremely low activity of the amidase toward acrylamide. We sought optimum culture conditions for the formation of nitrile hydratase by Brevibacterium sp. CH1. The effects of temperature and pH on the activity of free and immobilized tells were investigated. The nitrite hydratase of Brevibacterium sp. CH1 acted not only on various aliphatic nitrites such as acrylonitrile, propionitrile and acetonitrile, but also on aromatic nitrile as nicotinonitrile.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.7
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• pp.676-681
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• 2010

Antibiotic resistant bacteria were isolated from livestock wastes and the resistance patterns were investigated using various antibiotic agents. Also, a gamma ray was tested regarding the aspects of the effect on resistance pattern and the efficiency of disinfection. Among the isolates, Esherichia coli and Brevibacterium sp. showed the most serious resistance patterns. Esherichia coli had resistance against 9 agents whereas Brevibacterium sp. against 7 agents. It can be suggested from these results that the abuse of antibiotic agents will cause a serious mutation problem even to Esherichia coli which is ubiquitous in the ecosystem. Esherichia coli could be easily controlled but Brevibacterium sp. had a moderate resistance to the gamma ray under low doses. In the case of Brevibacterium sp, more than 2.0 kGy of a radiation dose will be required in order to achieve an enhanced efficiency of disinfection.

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.411-416
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• 1990

Microbiological conversion of sterols to 17-ketosteroids has been recongnized as a source for commerical preparation of steroidal drugs. For the purpose of strain development, we isolated microorganisms through enrichment culture method and identified an isolate strain. The strain was closely related to Brevibacterium ergthrogenes. The optimal conditions for 1, 4-androstadiene-3, 17-dione (ADD) formation were as follows; pH 7.4, lactose 0.2%, beef extract 0.2%, bentonite 0.5% in the chlolesterol fermentation medium. Maximum production was obtained with the addition of $\alpha$, $\alpha$'-dipyridyl (1 mM, final conc.) at 17-20 hours after incubation.

• Microbiology and Biotechnology Letters
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• v.18 no.1
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• pp.56-60
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• 1990

A bacterial strain of Brevibacterium sp. CHI was isolated from soil and used to produce an enzyme (nitrile hydratase) necessary for carrying out the bioconversion of acrylonitrile to acrylamide. Various immobilization methods and enzyme stability were investigated. The nitrile hydratase showed the maximum stability at pH 7 for the free cells. EDTA and phenyl methyl sulfonyl fluoride were selected as the protease inhibitor and the enzyme stability was evaluated by changing inhibitor concentration. Acrylamide beads were the best carriers among four carriers we tested in terms of stability and physicoehemical strength. The storage stability of the immobilized cells decreased with increasing acrylamide concentration of the gel phase at 4$^{\circ}C$, and was very low at acrylarnide concentration above 25%.

• Microbiology and Biotechnology Letters
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• v.30 no.2
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• pp.105-110
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• 2002

The sequence of 3,221 nucleotides immediately adjacent to rpsA gene encoding 30S ribosomal protein S1 of Brevibacterium ammoniagenes was determined. A putative open reading frame (ORF) of 2,670 nucleotides for a polypeptide of 889 amino acid residues and a TAG stop codon was found, which is located at a distance of 723 nucleotides upstream from rpsA gene with same translational direction. The deduced amino acid sequence of the ORF was found to be highly homologous to the DNA polymerase I of Streptomyces griseus (75.48％), Rhodococcus sp. ATCC 15963 (56.69％), Mycobacterium tuberculosis (55.46％) and Mycobacterium leprae (53.99％). It was suggested that the predicted product of the ORF is a DNA polymerase I with three functional domains. Two domains of 5 → 3 exonuclease and DNA polymerase are highly conserved with other DNA polymerase I, but 3 → 5 exonuclease domain is less conserved.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.802-805
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• 2001

The dapD gene of Brevibacterium lactofermentum encoding tetrahydrodipicolinate N-succinyl transferase, one of the enzymes involved in lysine biosynthesis, was cloned by complementation of Escherichia coli dapD mutnat. The recombinant plasmid pLS1 was found to contain a 3.6 kb DNA fragment. Southern hybridization analysis confirmed that the cloned DNA fragment originated from B. lactofermentum. The data of L-lysine production showed that the B. lactofermentum dapD gene was expressed in E. coli.