• Food Science and Biotechnology
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• 제15권4호
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• pp.595-598
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• 2006

Semi-quantitative monitoring of Lactobacillus sake and Lactobacillus plantarum, major and minor microorganisms in kimchi, respectively, and Lactobacillus paraplantarum, recently shown to be present in kimchi, was carried out by real-time polymerase chain reaction (PCR). Changes in the 3 species during kimchi fermentation were monitored by the threshold cycle ($C_T$) of real-time PCR. As fermentation proceeded at $15^{\circ}C$, the number of L. sake increased dramatically compared to those of L. plantarum and L. paraplantarum. During fermentation at $4^{\circ}C$, the growth rates of the 3 species decreased, but the proportions of L. plantarum and L. paraplantarum in the microbial ecosystem were almost constant. Considering the $C_T$ values of the first samples and the change in the $C_T$ value, the number of L. sake is no doubt greater than those of L. plantarum and L. paraplantarum in the kimchi ecosystem. L. sake seems to be one of the major microorganisms involved in kimchi fermentation, but there is insufficient evidence to suggest that L. plantarum is the primary acidifying bacterium.

• 한국미생물·생명공학회지
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• 제37권1호
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• pp.24-32
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• 2009

숙성 정도가 오래된 김장 배추 김치에서 분리되어 16S rDNA 염기 서열 분석을 통해 부분 동정된 KNUC25 분리 균주를 단백질 전기 영동 패턴과 생리적 특징 그리고 염기 서열의 유사성을 비교하여 Lactobacillus paraplantarum로 동정하였다. L. paraplantarum KNUC25의 농축 상등액은 그람 양성균과 음성균에 넓은 범위의 항균 활성을 나타냈다. 전자 현미경을 통해 KNUC25가 만들어내는 항균 물질은 세균의 표면에 작용하여 생육을 억제하는 것으로 확인되었다. 항균 활성 물질을 생산하는 최적 온도는 섭씨 30도이고, 높은 온도에서도 항균 활성을 보였으며 단백질 분해 효소에 안정하며 비단백질성 항균 물질일 가능성을 보여주었다.

• 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.

• 한국미생물·생명공학회지
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• 제36권4호
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• pp.247-259
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• 2008

미생물 구조 및 집단 구성원의 변화를 배양에 의존하지 않고, 빠르게 평가할 수 있는 방법의 하나인 terminal-restriction fragment length polymorphism (I-RFLP) 분석을 김치 유산균 연구에 적용하여, $15^{\circ}C$ 및 $4^{\circ}C$ 발효 김치에 관여하는 유산균의 다양성과 역동성을 검토하였다. 두 발효온도에서 공통적으로 Leuconostoc mesenteroides, Lc, inhae, Lc. kimchii, Weissella koreensis, W. cibaria, Lactobacillus sakei, Lb. curvatus, Lb. plantarum, Lb. paraplantarum, Lb. pentosus, 및 Lb. brevis의 존재가 예상되었고, Lc. citreum과 Enterococcus faecalis는 각각 $15^{\circ}C$와 $4^{\circ}C$에서 검출되었다. W. koreensis는 중기발효에 우점을 점하였고, Lactobacillus 속은 발효 후기의 우점종으로 나타났다. Lb. sakei, Lb. curvatus는 발효온도에 관계 없이 우점종을 형성하였지만, Lb. plantarum, Lb. paraplantarum, Lb, pentosus와 Lb. brevis의 생육은 저온에서 잘 일어나지 않았다. 몇 종의 Leuconostoc 속 유산균은 발효 후기까지 생장이 유지되었다.

• Journal of Microbiology and Biotechnology
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• 제17권2호
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• pp.287-296
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• 2007

A Lactobacillus paraplantarum strain producing a bacteriocin was isolated from kimchi using the spot-on-the lawn method and named L. paraplantarum C7 [15]. The bacteriocin, paraplantaricin C7, was found to inhibit certain Lactobacillus strains, including L. plantarum, L. pentosus, and L. delbrueckii subsp. lactis. It also inhibited Enterococcus faecalis, yet did not inhibit most of the other LAB (lactic acid bacteria) tested. The maximum level of paraplantaricin C7 activity was observed under the culture conditions of $25^{\circ}C$ and a constant pH of 4.5. Paraplantaricin C7 retained 90% of its activity after 10 min of treatment at $100^{\circ}C$ and remained stable within a pH range of 2-8. Based on a culture supernatant, paraplantaricin C7 was purified by DEAE-Sephacel column chromatography and $C_{18}$ reverse-phase HPLC. SDS-PAGE and activity staining were then conducted using the purified paraplantaricin C7, and its molecular mass determined to be about 3,800 Da. The 28 N-terminal amino acids from the purified paraplantaricin C7 were determined, and the structural gene encoding paraplantaricin C7, ppnC7, was cloned by PCR using degenerate primers based on the N-terminal amino acid sequence. The nucleotide sequences for ppnC7 and other neighboring orfs exhibited a limited homology to the previously reported plantaricin operon genes. Paraplantaricin C7 is a novel type II bacteriocin containing a double glycine leader sequence.

• Journal of Microbiology and Biotechnology
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• 제14권5호
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• pp.1071-1074
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• 2004

The effect of preadaptation at low temperature on cryoprotection was studied for Lactobacillus paraplantarum C7, a bacteriocin producer isolated from kimchi. L paraplantarum C7 cells in their log growth phase were incubated at $15^\circ{C}$, $10^\circ{C}$, or $5^\circ{C}$ for 2, 4, and 6 h, respectively, before being frozen at $-70^\circ{C}$. After 24 h of freezing, viable cells were counted after brief thawing. The freezing-thawing cycles were repeated three more times. Cells preadapted at $10^\circ{C}$ or $5^\circ{C}$ before freezing survived better than control cells, but preadaptation at $15^\circ{C}$ did not confer cryoprotection. Chloramphenicol addition did not destroy the cryoprotection, indicating that protein synthesis was not required for the development of cryoprotection. SDS-PAGE showed induction of a 6.5-kDa protein, a major cold-shock protein, in preadapted cells.

• Journal of Microbiology and Biotechnology
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• 제17권5호
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• pp.822-829
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• 2007

A gene coding for phosphoketolase, a key enzyme of carbohydrate catabolism in heterofermentative lactic acid bacteria(LAB), was cloned from a Lactobacillus paraplantarum C7 and expressed in Escherichia coli. The gene is 2,502 bp long and codes for a 788-amino-acids polypeptide with a molecular mass of 88.7 kDa. A Shine-Dalgarno sequence(aaggag) and an inverted-repeat terminator sequence are located upstream and downstream of the phosphoketolase gene, respectively. The gene exhibits an identity of >52% with phosphoketolases of other LAB. The phosphoketolase of Lb. paraplantarum C7(LBPK) contains several highly conserved phosphoketolase signature regions and typical thiamine pyrophosphate(TPP) binding sites, as reported for other TPP-dependent enzymes. The phosphoketolase gene was fused to a glutathione S-transferase(GST::LBPK) gene for purification. The GST::LBPK fusion protein was detected in the soluble fraction of a recombinant Escherichia coli BL21. The GST::LBPK fusion protein was purified with a yield of 4.32mg/400ml by GSTrap HP affinity column chromatography and analyzed by N-terminal sequencing. LBPK was obtained by factor Xa treatment of fusion protein and the final yield was 3.78mg/400ml. LBPK was examined for its N-terminal sequence and phosphoketolase activity. The $K_M\;and\;V_{max}$ values for fructose-6-phosphate were $5.08{\pm}0.057mM(mean{\pm}SD)$ and $499.21{\pm}4.33{\mu}mol/min/mg$, respectively, and the optimum temperature and pH for the production of acetyl phosphate were $45^{\circ}C$ and 7.0, respectively.

• 한국미생물·생명공학회지
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• 제36권2호
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• pp.96-100
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• 2008

recA 유전자를 특이적으로 증폭하는 PCR을 이용하여 우리나라 전통 침채류 발효에 관여하는 유산균의 다양성을 검토해 보았다. 김치에서 많이 검출되는 유산균 7종 및 대조군으로 Lactobacillus acidophilus를 검출할 수 있는 특이적 PCR primer pair을 이용하여 전통 침채류 5증(갓김치, 동치미, 배추김치, 오이소박이, 총각김치로부터 추출한 DNA를 template로 PCR을 수행한 결과, 5종의 침채류 모두에서 Lactobacillus plantarum과 Lactobacillus sakei가 검출되었지만, Lactobacillus paraplantarum, Lactobacillus pentosus와 대조군인 Lb. acidophilus는 검출되지 않았다. Lactobacillus brevis와 Leuconostoc citreum은 배추김치에서만 검출되었으며, Leuconostoc mesenteroides의 경우 갓김치, 동치미, 배추김치, 오이소박이에서 검출되었다. 주재료의 종류에 따라서 발효에 관여하는 유산균은 차이가 있는 것으로 추정되며, Lb. plantarum과 Lb. sakei가 우리나라 침채류 발효에 가장 널리 관여하는 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제17권7호
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• pp.1213-1216
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• 2007

The vector pCW5 with plasmid pC7, originally isolated in Lactobacillus paraplantarum C7 derived from kimchi, was constructed using a p32 strong promoter, the pC7 replicon, and green fluorescent protein (GFP) as the reporter. The constructed vector was transformed into E. coli and Leuconostoc mesenteroides, and GFP expression detected using a Western blot analysis. GFP fluorescence was recognized in E. coli and Leuconostoc mesenteroides using a confocal microscope. In addition, GFP fluorescence was also clearly detected in several industrially important lactic acid bacteria (LAB), including Lactobacillus bulgaricus, Lactobacillus paraplantarum, and Lactobacillus plantarum. Thus, pCW5 was shown to be effective for Leuconostoc mesenteroides when using GFP as the reporter, and it can also be used as a broad-host-range vector for other lactic acid bacteria.

• 한국미생물·생명공학회지
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• 제37권2호
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• pp.91-98
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• 2009

김치 소비가 증가하면서 공장에서 큰 규모로 만들어지게 되었다. 그래서 상업용 김치의 위생 상태는 주 관심사가 되었다. 충분히 발효되지 않은 상업용 김치로부터 17종의 대장균유사세균(coliform bacteria)을 분리하였다. 16S rDNA 분석에 의하여 Enterobacter intermedius, Ent. cloacae, Ent. amnigenus, Klebsiella terrigena, K. ornithinolytica, K. oxytoca, Hafnia alvei 등의 3속 7종으로 부분 동정되었다. 한편, 오래된 배추김치로부터 Lactobacillus paraplantarum KNUC25라고 부분 동정된 젖산균이 분리되어 그의 항미생물 활성이 보고되었다. 이 균주는 spot-on the lawn test와 세포생존실험을 통하여 본 연구에서 분리한 대장균유사세균과 몇몇 유해한 대장균유사세균에 대하여 항세균 활성을 보여 주었다. 상업용 김치에 있는 대장균유사세균은 L. paraplantarum KNUC25균주 배양 상층액의 첨가에 의하여 효과적으로 억제되었다.