• 한국미생물·생명공학회지
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• 제47권4호
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• pp.546-554
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• 2019

This study, for the first time, reports the functional expression of lipase B derived from the yeast Candida antarctica (CALB) in Corynebacterium strain using the Escherichia coli plasmid PK18. The CALB gene fragment encoding a 317-amino-acid protein was successfully obtained from the total RNA of C. antarctica. CALB was readily produced in the Corynebacterium strain without the use of induction methods described in previous studies. This demonstrated the extracellular production of CALB in the Corynebacterium strain. CALB produced in the Corynebacterium MB001 strain transformed with pEC-CALB recombinant plasmid exhibited maximum extracellular enzymatic activity and high substrate affinity. The optimal pH and temperature for the hydrolysis of 4-nitrophenyl laurate by CALB were 9.0 and 40℃, respectively. The enzyme was stable at pH 10.7 in the glycine-KOH buffer and functioned as an alkaline lipase. The CALB activity was inhibited in the presence of high concentration of Mg²⁺, which indicated that CALB is not a metalloenzyme. These properties are key for the industrial application of the enzyme.

• 한국미생물·생명공학회지
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• 제24권6호
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• pp.699-704
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• 1996

About 600 microorganisms isolated from soil, marsh, compost, etc. were examined for their flocculating ability in the kaolin suspension and swine wastewater. Among them, K-199 was the best producer of flocculant and was identified to be a species belong to the genus Corynebacterium. The maximum production of the flocculant from Corynebacterium sp. K-199 was observed in culture medium containing 2% glycerol, 0.4% peptone, 0.3% K$_{2}$HPO$_{4}$, 0.1% CaCO$_{3}$, 0.05% NaCl, 0.1% yeast extract, 0.1% MgSO$_{4}$,7H$_{2}$O and initial pH 7.5 when cultured with rotary shaker controlled at 25$\circ$C and 150 rpm. Under the optimal culture condition with jar fermentor, the maximum production was reached to flocculating activity of 780 units/ml after 4 days. From the results of the activity be fully maintained by periodate oxidization, it suggests that the activity is due to the protein.

• Journal of Microbiology and Biotechnology
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• 제11권5호
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• pp.819-824
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• 2001

The principal DNA modification systems of the amino-acid-producing bacteria Corynebacterium glutamicum AS019, Brevibacterium flavum BF4, and B. lactofermentum BL1 was investigated using two approaches; digestion of plasmid DNA isolated from these species TseI and Fnu4HI, and sequence analysis of the putative methyltransferase target sites following the derivatization of DNA using metabisulfite treatment. The C. glutamicum and B. flavum strains showed similar digestion patterns to the two enzymes, indicating that the target for cytidine methyltransferase recognizes 5'-GCSGC-3'(where S is either G or C). Mapping the methylated cytidine sites by bisulfite derivatization, followed by PCR amplification and sequencing, was only possible when the protocol included an additional step eliminating any underivatized DNA after PCR amplification, thereby indicating that the derivatization was not $100\%$ efficient. This may have been due to the high G0C content of this genus. It was confirmed that C. glutamicum AS019 and B. flavum BF4 methylated the cytidine in the $Gm^5CCGC$ sequences, yet there were no similar patterns of methylation in B. lactofermentum, which was consistent with the distinctive degradation pattern seen for the above enzymes. These findings demonstrate the successful application of a modified bisulfite derivatization method with the Corynebacterium species for determining methylation patterns, and showed that different species in the geneus contain distinctive restriction and modification systems.

• 미생물학회지
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• 제12권1호
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• pp.37-51
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• 1974

Three strains which accumulated large quantities of L-hlutamic acid as the chief product of metabolism in the presence of glucose and inorhanic ammonium salt under the aerobic condition sere newly isolated. These strains have the general characters as follows: Gram-positive, short fod-shaped, non-sporulating, non-motile, and facultative anaerobe. A change of cell shates was not almost observed in their life cycles and neither a phenomenon of cell-elongation nor a pleomorphism was recognized in any cases. Together with rigid stability in Gram-stain, these characters as above indicated evidences that newly isolates would belong to genus Brevibacterium clearly differentiated from genus Corynebacterium. At the same time the newly isolates, in addition to nutritional requirement of biotin and thiamine, showed the distinctive character of requirement of special amino acid such as histidine or cysteine for their considerable growth. These physiological characters including nitrates reduction, reaction on milk, and slow formation of acid from sugar also were useful in confirming that these bacteria would be Brevibacterium ammoniagenes.

• 미생물학회지
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• 제38권2호
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• pp.57-61
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• 2002

전라남도 장흥군 인근 해안에서 채집한 불가사리(Asterias amurensis)를 대상으로 불가사리의 장내에 분포하는 종속영양세균의 균체수를 측정하였고, 분리동정된 균주들을 대상으로 탄소원 이용 특성을 조사하였다. 불가사리의 장내에 분포하는 종속영양세균의 균체수는8.65$\pm$0.65 $\times$$10^3$ cfu . g$^{-1}$이 였으며, 분리 동정된 24균주(그람음성균 11균주, 그람양성균이 13균주)중에서 Vibrio속,Staphylococcus속, Corynebacterium속이 높게 나타났다. 불가사리 장내에서 분리 동정된 세균들은 그람양성의 간균이 높은 비율을차지하였고, catalase와 oxidase의 활성은 각각 54.2%,20.8%로 나타났다. 그람음성균의 경우, 탄소원으로 glucose의 이용률이 가장 높았고, 그 다음으로 sucrose, mannose, maltose,그리고 trehalose의 순으로 높은 이용률을 나타냈으며, adipate, phenol acetate는 이용하지 못하였다. 그람양성균의 경우, glucose가 가장 높은 이용률을 나타냈고, 그 다음은 fructose, trehalose, maltose 순으로 높은 이용률을 보였다.

• Journal of Species Research
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• 제11권1호
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• pp.1-9
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• 2022

The phylum Actinobacteria includes many groups of aerobic, Gram-stain-positive, rod, or filamentous shaped bacteria. Actinobacteria are known for multicellular differentiation in some groups, and also for production of various secondary metabolites such as antibiotics. During a series of extensive surveys of indigenous prokaryotic species diversity in Korea, bacterial strains belonging to Actinobacteria were isolated from various sources of terrestrial environments. A total of 21 bacterial strains, belonging to 10 genera in 8 families, were isolated as unrecorded species in Korea. Among them, 11 were assigned to the family Streptomycetaceae, two species assigned to each of the families Microbacteriaceae, Mycobacteriaceae and Nocardioidaceae, and one species assigned to each of the families Euzebyaceae, Corynebacteriaceae, Micrococcaceae and Intrasporangiaceae. At the genus level, Streptomyces (10 species) was the most abundant, followed by Microbacterium and Mycolicibacterium(2 species each), and one species in each of the genera Corynebacterium, Euzebya, Arthrobacter, Terracoccus, Kribbella, Nocardioides and Yinghuangia. The detailed descriptions of each unrecorded species are provided.

• 한국수산과학회지
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• 제25권4호
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• pp.314-321
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• 1992

1990년 2월부터 12월에 걸쳐 곡포 인근수역에서 김 엽체를 채취하여 김 엽체에 부착된 종속영양 세균의 분포와 계절적 속조성의 변화를 미생물 생태학적 측면에서 조사 비교하였다. 김 엽체에 부착한 종속영양 세균의 년중 분포는 정점 1에서 $6.9\times10^2-1.04\times10^5\;cfu/cm^2$, 정점 2에서 $9.4\times10^3-2.93\times10^5\;cfu/cm^2$ 범주에서 변화하였으며, 조사기간 중 김 엽체에서 분리된 세균의 특성을 살펴보면 간균이 평균 $65\%$를, 그람음성이 $52.1-82.7\%$를 차지하였다. 분리된 균중 $68\%$는 3월에 전분분해능을 나타냈으나 전반적으로 탄소원의 이용은 빈약했으며 $H_2S$ 생성을 하지 않았다. 김 엽체에서 분리된 세균 중 우점속은. 3월의 경우 Alcaligenes spp., Moruella spp.가 우점속으로 나타났으며, 11월의 경우 Microcaccus spp., Moraxella spp., Corynebacterium spp.이 우점속으로 나타났다.

• 한국식품과학회지
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• 제28권2호
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• pp.260-266
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• 1996

개량식 고추장과 재래식 고추장에 사용되는 코지 및 메주와 각 고추장의 숙성중 분리 등정된 세균군의 분포를 조사한 결과는 다음과 같다. 개량식 고추장의 경우 소맥코지, 콩코지 및 발효숙성 과정 중에서 세균은 7속 14종이 분리 동정되었으며 숙성 말기에서는 3속 6종만이 분리되었다. 소맥코지에서는 B. subtilis가 30%, 콩코지에서는 B. licheniformis가 74%, B. subtilis가 12%, 소맥코지와 콩코지를 혼합배양한 개량식 메주에서는 B. lucheniformis가 40%, B. subtilis가 10%로 우세한 분포를 보였다. 콩코지에서 우세 세균종인 B. licheniformis가 발효숙성에서도 우세하게 분포되었고 B. subtilis와 함께 각 숙성과정에서 Bacillus속 2종이 $56{\sim}70%$의 분포비율을 보였다. 재래식 추장의 메주 및 발효숙성 과정 중에서는 10속 19종이 분리되었으며 숙성 완료기인 12개월 후에도 5속 8종이 분리되어 개량식보다 다양한 세균분포를 보임으로써 기존의 Bacillus속 위주의 연구보고와 상이한 결과를 나타내었다. 재래식 메주에서는 우점하고 있다고 보여지는 균종은 없었으며 6속 8종이 유사한 수준으로 분포하고 있었고 발효숙성 중에는 Bacillus속의 분포비가 $38{\sim}80%$를 보였으나 개량식과는 달리 우세 균종인 B. subtilis가 $24{\sim}46%,$ B. licheniformis가 $4{\sim}18%$fmf 차지하였다. B. subtilis 및 B. licheniformis로 동정된 균주들 중 효소활성 및 생육특성 등 생리적 성질의 차이에 의해 각각 3가지 군으로 대별할 수 있었으며 생리적으로 상이한 특성을 가진 strain들을 분리할 수 있었다. 본 실험의 결과는 고추장 제조 표준화를 위한 세균학적인 측면에서 기초자료로 활용될 수 있다고 하였으며 향후 각 균종의 발효숙성에 기여하는 역할규명을 위한 연구와 고찰이 필요하다.

• 한국치위생학회지
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• 제18권5호
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• pp.843-852
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• 2018

Objectives: The study aimed to isolate the abundant bacteria in dental caries in children and to investigate the bacterial species involved in addition to those that have been previously reported. Methods: The specimens were collected from the supragingival plaques of each dental caries area, pit and fissure caries, deep dentinal caries, smooth surface caries, and dental caries, and from healthy subjects in the control group. Bacteria were cultured from these specimens, DNA was extracted from the isolated bacteria, and the 16S rRNA gene sequences were analyzed and identified. Results: Based on the results of the 16S rRNA gene sequence analysis for the 90 strains of dominant bacteria from the 45 specimens, 5, 7, 8, 7, and 13 species were identified from the supragingival plaques from healthy teeth, pit and fissure caries, deep dentinal caries, smooth surface caries, and dental caries, respectively. In healthy teeth, Actinomyces naeslundii dominated. Corynebacterium durum, Ralstonia pickettii, and Streptococcus intermedius showed equal distribution. The dominant bacterial species in dental caries, S. sanguinis, showed the greatest difference in prevalence in pit and fissure caries. In deep dentinal caries, S. mutans and Lactobacillus rhamnosus were dominant; in smooth surface caries, S. mutans and S. sanguinis were dominant; and in the supragingival plaques of dental caries, S. sanguinis and S. mutans were dominant. Conclusions: The bacterial species isolated from dental caries encompassed four phyla, eight genera, and 22 species. In addition, the SS1-2 strain, belonging to the genus Neisseria, was identified as a new species from among the isolated strains.

• 환경생물
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• 제38권3호
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• pp.433-449
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• 2020

Nine fish and one clam species were collected from freshwater environments in Korea, including four lakes, two streams, and the Nakdong River, to investigate the host-associated bacteria. Hundreds of bacterial strains were isolated from the samples using a cell sorter and a dilution plating method. After identification of the bacterial strains using 16S rRNA gene sequences, 42 strains with greater than 98.7% sequence similarity with validly published species were determined to be unrecorded bacterial species in Korea. These strains were phylogenetically diverse and assigned to four phyla, six classes, 17 orders, 27 families, and 32 genera. At the genus level, the unrecorded species were classified as Corynebacterium, Mycobacterium, Mycolicibacterium, Gordonia, Williamsia, Modestobacter, Brachybacterium, Sanquibacter, Arthrobacter, and Mycolicibacterium of the class Actinobacteria; Empedobacter, and Flavobacterium of the class Flavobacteriia; Fictibacillus, Psychrobacillus, Cohnella, Paenibacillus, Rummeliibacillus, Enterococcus, and Vagococcus of the class Bacilli; Aquamicrobium, Paracoccus, and Sphingomonas of the class Alphaproteobacteria; Achromobacter, Delftia, and Deefgea of the class Betaproteobacteria; and Aeromonas, Providencia, Yersinia, Marinomonas, Acinetobacter, and Pseudomonas of the class Gammaproteobacteria. The 42 unrecorded species were subjected to further taxonomic characterization using gram staining, cellular and colony morphological determination, biochemical analyses, and phylogenetic analyses. This paper provides detailed descriptions of the 42 previously unrecorded bacterial species.