• Journal of Microbiology and Biotechnology
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• 제21권4호
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• pp.421-429
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• 2011

For precise identification of a Lactobacillus K1 isolate, LC-MS/MS analysis of the putative surface layer protein was performed. The results obtained from LTQ-FT-ICR mass spectrometry confirmed that the analyzed protein spot is the surface layer protein originating from Lb. helveticus species. Moreover, the identified protein has the highest similarity with the surface layer protein from Lb. helveticus R0052. To evaluate the proteomic study, multilocus sequence analysis of selected housekeeping gene sequences was performed. Combination of 16S rRNA sequencing with partial sequences for the genes encoding the RNA polymerase alpha subunit (rpoA), phenylalanyl-tRNA synthase alpha subunit (pheS), translational elongation factor Tu (tuf), and Hsp60 chaperonins (groEL) also allowed to classify the analyzed isolate as Lb. helveticus. Further classification at the strain level was achieved by sequencing of the slp gene. This gene showed 99.8% identity with the corresponding slp gene of Lb. helveticus R0052, which is in good agreement with data obtained by nano-HPLC coupled to an LTQ-FT-ICR mass spectrometer. Finally, LC-MS/MS analysis of surface layer proteins extracted from three other Lactobacillus strains proved that the proposed method is the appropriate molecular tool for the identification of S-layer-possessing lactobacilli at the species and even strain levels.

• Journal of Microbiology and Biotechnology
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• 제15권2호
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• pp.428-433
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• 2005

A bacteriocin-producing lactic acid bacterium with inhibitory activity against the growth of Lactobacillus plantarum was isolated from kimchi, a traditional Korean fermented vegetable. For the identification of the isolate, its 16S rDNA was sequenced. As a result, the sequence showed $99\%$ homology with those from Lactobacillus paraplantarum, Lb. plantarum, and Lactobacillus pentosus. For further identification of the isolate, the sequence of its 16S/23S rDNA spacer region was determined, and the sequence matched perfectly with that of Lb. paraplantarum. SDS­PAGE fingerprinting of whole-cell proteins of the isolate was almost identical with that of Lb. paraplantarum. The isolation and identification of Lb. paraplantarum suggest that Lb. paraplantarum is one of the lactic acid bacteria involved in kimchi fermentation.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2002년도 학술발표대회
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• pp.73-74
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• 2002

• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.558-562
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• 2010

SDS-PAGE of extracted surface-associated proteins of Lactobacillus rhamnosus strains E/N, Oxy, and Pen, was performed. The obtained protein patterns allowed differentiation of the examined strains, which was not accomplished by the commonly used RAPD genotypic method. The differentiation by the SDS-PAGE method proved to be a useful tool for strain-specific identification, which was further confirmed by 2DE analysis. Therefore, it can be used as an alternative or complementary method for both conventional and genotypic identification procedures, especially when closely related lactobacilli isolates are identified.

• 한국축산식품학회지
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• 제24권2호
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• pp.164-170
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• 2004

건강한 성인의 분변으로부터 담즙산 분해능이 우수한 젖산균의 분리를 위하여 무작위 선별법과 도말법을 사용하여 층 120주의 젖산균을 1차 분리하였고, 그중 5종의 젖산균을 최종 선발하였다. 유용한 젖산균이 갖추어야할 중요한 성질인 내산성, 내담즙산성, 대장균 저해능을 시험한 결과 Lactobacillus sp. CK 102이 가장 우수한 균주로 나타났다. Lactobacillus sp. CK 102 균주는 pH 2.0에서 68％ 이상의 내성과 1.0％ 담즙산이 함유된 배지에서 90％이상의 내성을 나타냈으며 MRS 배지에서 대장균과 혼합 배양시 18시간 이내에 대장균을 100％ 사멸시켰다. 젖산균제로써 기능이 가장 우수한 균주인 Lactobacillus sp. CK 102를 API kit와 16S rRNA sequencing 방법을 사용하여 동정한 결과 Lactobacillus platarum 으로 밝혀졌다. 이상의 결과에서 분리한 Lactobacillus sp. CK 102는 생균제로서 안전하게 이용할 수 있는 것으로 나타났다.

• 한국가금학회지
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• 제27권1호
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• pp.31-35
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• 2000

This study was investigated to observe Lactobacillus spp. population of poultry digestive organ, duodenum, ilium, cecum and colon by growing steps and to select of valuable lactobacilli as probiotics. Two strains of male broiler commercial chickens, Hybrid and Ross, were used to evaluate population of Lactobacillus spp. in intestinal tracts. Three strains of Lactobacillus were identified, and bile salts environment. The number of lactovacilli was the lowest in duodenum compared to other intestinal tracts which had similar population. Population of Lactobacillus was maintained constantly regardless growing steps after one week of age. Identification of Lactobacillus from cecum resulted in L.reuteri BC5, L. crispatus BC7, L.reuteri BC9. All strains was depressed in pH 1 and 2, although two strains could survive for one hour at pH 2. And they could survive at pH 4 for 4hours. In bile salts tolerance, L.reuteri BC5, L.crispatus BC7 were maintained for 2 hours, but the growth reduced from 2hours. Growth of L.reuteri BC9 was increased continuously. In conclusion, Lactobacillus of intestinal tracts were established at first week, and maintained constant population. They were influenced on severe acidic condition and bile salts. Cecal Lactobacillus has different growth charcteristics by strains.

• 한국식품영양학회지
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• 제10권3호
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• pp.350-359
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• 1997

백김치를 담근 후 15$^{\circ}C$에서 60일간 밀폐상태로 발효시키면서 발효일수 경과에 따른 pH, 총산함량 및 미생물수의 변화를 조사하고, 주요 미생물군집을 분리.동정하였다. 담금 즉시의 김치는 pH 6.15, 총산 0.03%였고, Gram 음성 간균류가 치우점 미생물이었으며 이들의 주요 속 구성은 Pseudomonas 55%, Enterobacter 40%, Erwinia 5%였다. 젖산균은 발효 2일 이후부터 최우점 미생물이 되었으며, 발효 4일, 12일 및 50일에 젖산균의 1차, 2차 및 3차 정상기를 각각 나타내었다. 젖산균 2차 정상기의 김치는 pH 3.51, 총산 0.59%로 적숙상태에 해당되며, 이 때 주요 젖산균의 종 구성은 Lactobacillus bavaricus 55%, Leuconostoc mesenteroides subsp. mesenteroides 42.5%, Leuconostoc paramesenteroides 2.5%였다. 젖산균 3차 정상기의 김치는 pH 3.40, 총산 1.10%로 과숙상태에 해당되며, 이 때 주요 젖산균의 종 구성은 Lactobacillus plantarum 65%, Lactobacillus brevis 35%였다. 젖산균들을 동정할 때에 Leuconostoc mesenteroides subsp. mesenteroides, Leuconostoc paramesenteroides, Lactobacillus plantarum 및 Lactobacillus brevis로 동정된 균주들은 기존의 분류체제에 비교적 잘 일치하였으나, Lactobacillus bavaricus로 동정된 균주들은 일치하지 않는 점들을 많이 나타내었다. 젖산균의 수가 증가할 때에 효모의 수가 감소하였고, 젖산균의 수가 감소할 때에 효모의 수가 증가하였다. 효모의 정상기는 젖산균이 제2정상기와 제3정상기의 사이인 30일에 나타났으며, 이 때 주요 효모의 속은 모두 Saccharomyces였다.

• 한국미생물·생명공학회지
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• 제28권2호
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• pp.124-127
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• 2000

Beneficial bacteria, which have been used for medical purpose and for medicines for treating intestinal disorders, include strains of Bifidobacterium sp., Lactobacillus sp., Enterococcus sp., Clostridium butyricum, Lactobacillus sporogenes, Bacillus subtilis, Bacillus polyfermenticus and the like. Bacillus polyfermenticuss SCD with is commonly called as Bispan strain has been appropriately used for the treatment of long-term intestinal disorders, since the live strains in the form of active endospores can successfully reach the target intestine. In this study, the identification and characterization of Bispan strain was done using SEM observation, API 50CHB kits, isoprenoid quinone analysis, and fatty acid analysis. These results suggest that Bispan strain is very similar to Bacillus subtilis.

• 한국식생활문화학회지
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• 제16권4호
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• pp.354-360
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• 2001

A Lactic acid bacterium for barley bread was isolated from barley powder and was identified as Enterococcus sp. It was used as a starter for barley bread and quality of bread was compared with the bread prepared by conventional starter 1. The pH of bread making process using Lactobacillus sanfrancisco starter was the lowest among tested starters. while the titratable acidity(TTA) of the strain was the highest, followed by Enterococcus sp.. 2. In valorimeter value(v/v), control was 70, but dough using all starter was 60. The peak time and stability of dough using Lactobacillus sanfrancisco were the highest among tested starters. 3. Extensibility of dough using Enterococcus sp. was the highest among tested starters, followed by Lactobacillus sanfrancisco. Proper extensibility and maximum resistance were observed in Lactobacillus sanfrancisco.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.577-583
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• 1994

To classify Lactobacillus casei strains on the basis of difference in their chromosomal DNA sequence, we have performed polymerase chain reactions on their chromosomal DNA by using random primers, and followed by analyzing randomly amplified polymorphic DNA fragments. We also developed a mini-preparative method to isolate PCR-grade chromosomal DNA from Lacto- bacillus casei strains within 3 hours. Based on RAPD pattems by polymerase chain reactions with degenerated random primers, 4 Lactobacillus casei strains and 2 mutant strains were successfully discriminated. Results were very sensitive, strain-specific and reproducible. It was also reliable. These results suggest that RAPD may be applied efficiently for the identification of several Lactoba- cillus casei strains.