• Journal of Microbiology
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• 제41권1호
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• pp.7-15
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• 2003

Nine dichlorprop-degrading bacteria and three pairs of bacteria showing syntrophic metabolism of the herbicide were isolated from soils, and their genetic and phenotypic characteristics were investigated. Analysis of 16S rDNA sequences indicated that the isolates were related to members of the genera, Sphingomonas, Herbaspirillum, and Bradyrhizobium. Twelve different chromosomal DNA patterns were obtained by polymerase-chain-reaction (PCR) amplification of repetitive extragenic palindromic (REP) sequences from the 15 isolates. The isolates were able to utilize the herbicide dichlorprop as a sole source of carbon and energy and their dichlorprop derogative pathways were induced by the presence of dichlorprop. Most of the isolates and syntrophic pairs were able to degrade both (R)- and (S)-dichlorprop, but strain DP522 exhibited enantioselective degradation of (S)-dichlorprop. The isolates degraded 2,4-dichlorophenoxyacetic acid, 2-methyl-4-chlorophenoxyacetic acid , and mecoprop, in addition to dichlorprop. Oxygen uptake experiments indicated that most of the isolates degraded dichlorprop through 2,4-dichlorophenol.

• 미생물학회지
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• 제24권1호
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• pp.67-72
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• 1986

Aromatic hydrocarbon degrading bacteria were isolated from industrial waste by using an agar plate method. The isolate DY-1 was identified as Acinetobacter sp. and found to utilize phenanthrene as tis sole carbon source. THe bacteria were proved to produce salicylic acid as an intermediate from phenanthrene through naphthalene pathway, when the products in the culture were wxamined by thin-layer chromatography. THe $Phn^+$ genes were found to be involved in two plasmids of about 4 and 40kb which were lost and not detected in the DNA samples prepared from the mitomycin C-cured cells by a gel electrophoretic analysis.

• 한국식품영양과학회지
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• 제29권5호
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• pp.832-836
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• 2000

A bactirium prohibiting the growth of fungus Botrytis cineria KT 433 was isolate and identified from soil. The isolated strain was gram positive, aerobic bacteria with cream color, round and mucoid. It showed ord form of 0.45$\times$1.1 ${\mu}{\textrm}{m}$ at the cultivated for 24 hrs and the ellipsoided endospore wer observed after culting for 72 hrs. The optimum growth temperature and pH wer 35$^{\circ}C$ and pH 5.0~8.0, respectively. It could assimilate daxtrin, maltose, glucose, mannose, ribose and collobiose as a sole carbon source. The isolated was confirmed to be a Bacillus sp. strain from the findings. The antibiotic from the isolated strain was stable up to 121$^{\circ}C$. The strain, especially, showed specific activity for mold and yeast. However, there was not significant antibacterial activity.

• Archives of Pharmacal Research
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• 제20권6호
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• pp.519-524
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• 1997

Steroid $9{\alpha}$-hydroxylase is an enzyme found in nocardioform microorganisms which can utilize steroids as a sole carbon source. After fractional centrifugation of the cell homogenates, the enzyme activity in Nocardia and Rhodococcus was found in cytoplasmic membrane fraction. On the contrary, Mycobacterium had its 9.alpha.-hydroxylation activity in cytosolic fraction. To characterize the enzyme in these microorganisms, several potential inhibitors of 9.alpha.-hydroxylase were tested and the cofactor requirement for the same enzyme was also examined. The inhibitory effect of ferrous ion chelators indicated involvement of iron containing proteins in the 9.alpha.-hydroxylase system. On the other hand, metyrapone, an inhibitor known to be specific for cytochrome P450 interfered with the enzyme in Mycobacterium, but didn't inhibit the enzyme activity in Nocardia and Rhodococcus. While the $9{\alpha}$-hydroxylase system in Nocardia and Rhodococcus required NADPH, NADH was required as an election donor in Mycobacterium.

• 약학회지
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• 제36권4호
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• pp.315-320
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• 1992

The amino acid threonine was produced from glycine and ethanol in a reaction mixture using resting cells of a newly isolated gram-negative methylotrophic bacterium, capable of growth on methanol. The isolate could utilize $C_1$ compounds and a variety of multicarbon substrates as sole carbon and energy source. To obtain cells of isolate with high threonine producing activity, we investigated optimum cultural conditions. Optimal growth was at the initial concentration of 0.5%(v/v) methanol, at $30^{\circ}C$ and pH 7.0. The growth was not affected by antibiotics inhibiting cell wall synthesis, but was completely suppressed by those inhibiting protein synthesis. The optimum reaction conditions from threonine production by resting cells of this strain were found.

• Journal of Microbiology and Biotechnology
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• 제3권2호
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• pp.95-98
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• 1993

This study was carried out to isolate and characterize the mutant strains of Schwanniomyces castellii NRRL Y-2477. Mutants were prepared with the treatment of ethyl methane sulfonate. 2-deoxy-D-glucose resistant mutants were isolated and two mutants were selected based on their high production of amylolytic enzymes and their ability to ferment starch. The mutants selected had higher a-amylase and glucoamylase activities than the wild type strain from several other carbon sources. Especially, it was revealed that mutant strain M-9, when cultured in the presence of glucose as a sole carbon source, shows relatively high activities of a-amylase and glucoamylase compared to those of the wild type strain. In result, this mutant strain can be considered as a constitutive producer of amylolytic enzymes. To compare the ethanol production ability of wild type strain and of mutant strains selected, an alcohol fermentation was carried out using 100 g/l soluble starch. Mutant strain M-9 did not improve the direct alcohol fermentation of starch, despite its excellent amylolytic activities performance. On the other hand, mutant strain M-6 produced 37.9 g/l (4.8%, v/v) ethanol by utilizing about 82% of substrate.

• 한국식품영양과학회지
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• 제11권2호
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• pp.31-35
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• 1982

폐액으로 방류되는 두부 폐수(whey)를 이용하여 alcohol 발효를 실시하였으며 다음과 같은 결과를 얻었다. whey중(中)에 함유(含有)된 환원당은 약 0.71%로서 이당(糖)을 이용(利用)하며 l당(當) 최대(最大) 1.86 g의 ethanol이 생산(生産)되었으나 수률(收率)이 낮아서 경제성은 희박하다. 그러나 발효에 의해서 단백질과 당이 각각 94%, 81%만큼이나 감소한 결과(結果)로 미루어 보아 두부 폐수중(廢水中)의 유기물(有機物)을 alcohol 발효(醱酵)에 이용(利用)할 수 있음을 확인(確認)하였다.

• 한국미생물·생명공학회지
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• 제25권6호
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• pp.552-559
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• 1997

Fe (III) impurities in clay could be microbially removed by inhabitant dissimilatory Fe (III) reducing microorganisms. Insoluble Fe (III) in clay particles was leached out as soluble reductive form, Fe (II). The microorganisms removed from 10 to 45% of the initial Fe (III) when each sugar was supplemented to be in ranges of 1 - 5 % (w/w; sugar/clay). The microorganisms reduced 2.1 - 12.8 mol of Fe (III) per 100 mol of carbon in sugars metabolized when sugars such as glucose, maltose, and sucrose were used as sole carbon source. Bacillus sp. IRB-W and Pseudomonas sp. IRB-Y were isolated from the enrichment culture of the clay. The isolates were considered to participate in metabolizing organic compounds to fermentative intermediates with relatively little Fe (III) reduction at initial Fe (III) reduction process. By the microbial treatment, the whiteness of the clay was increased form 63.20 to 79.64, whereas the redness was obviously decreased form 13.47 to 3.55. This treatment did not cause any unfavorable modifications in mineralogical compositions of the clay.

• Preventive Nutrition and Food Science
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• 제5권4호
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• pp.194-196
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• 2000

A bacterium capable of producing polygalacturonase was isolated from kimchi, and identified as a strain of Bacillus. The effects of culture conditions and medium composition on enzyme production were investigated. Among the tested carbon sources, polygalacturonic acid or pectin was most effective for the production of the enzyme. Therefore, it seemed that the enzyme was induced when pectin or polygalacturonic acid was used as a sole source of carbon. The optimal concentration of polygalacturonic acid was 0.5%. For nitrogen sources, yeast extract was best for the production of the enzyme, at a level of 0.25%. The enzyme was maximally produced by cultivating the isolated Bacillus sp. at an initial pH of 88.0 and temperature of 45$^{\circ}C$ for 20 hours.

• Journal of Microbiology
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• 제35권1호
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• pp.30-39
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• 1997

Acinetobacter sp. strain JC1 DSM 3803, a carboxydobacterium, was found to grow methylotrophically at the expense of methanol and methlamine, but not of methane, formaldehyde, formate, dimethylamine, or trimethylamine, as the sole source of carbon and energy. The doubling times of the bacterium growing on methanol (0.5%, v/v) and methylamine (0.5%, w/v) at 3$0^{\circ}C$ and pH 6.8 were 4.8 h and 5.7 h, respectively. Cells grown on methanol, however, failed to show typical methanol dehydrogenase and oxidase activities. The cell was found to contain no c-type cytochromes. Cells grown on methanol exhibited higher catalase activity than those grown on pyruvate or glucose. The catalase present in the cells also exhibited peroxidase activity. The catalase activity, growth on methanol of the cell, and oxygen consumption by methanol-grown maldehyde dehydrogenase, formaldehyde reductase, glucose-6-phosphate dehydrogenase, and 6-phosphogluconate dehydrogenase activities were detected from cells grown on methanol.