• 한국식물병리학회지
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• 제10권3호
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• pp.157-162
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• 1994

Erwinia rhapontici causes soft-rot disease in a number of plants such as onion, garlic and hyacinth. There has been no report that E. rhapontici produces pectate lyase. Pel gene was cloned from genomic DNA of the parasitic soft-rot E. rhapontici polymerase chain reaction by using synthetic oligonulceotide primers designed from the pel 1 to E. carotovora. The recombinant plasmid pJE101 containing pectate lyase gene, when introduced into E. coli DH5$\alpha$, produced pectate lyase an macerated hyacinth tissue.

• 한국미생물·생명공학회지
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• 제22권1호
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• pp.65-72
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• 1994

Purification and characterization of pectate lyase from Bacillus sp HSA-925. Bacillus sp. HSA-925 isolated from soil produced constitutively an extracellular pectate lyase when cultivated in LB broth. The pectate lyase(EC 4.2.2.2) was purified from the cuylture broth by preciptation with ammonium sulfate, followed by column chromatography on CM-cellulose C-50 and repeated gel filtration on Sephadex G-75G. The enzyme had a molecular weight of 32-33 kDa. The activity was mazimum at pH 9.5 AND 45$\CIRC $C. The enzume activity was stable at 55$\circ $C for 15 min and between pH7-12. The activation energy, Km and V$_{max}$ for the pectate lyase were 5.8779 kcal/mol, 6.33$\times $10$^{-2}$ mol/ml and 2.09$\times $10$^{2}$ $\mu $mol/min respectively. The enzyme was activated by Ca$^{2+}$, Cu$^{2+}$ and inhibited by Li$^{+}$, Hg$^{2+}$, EDTA.

• 한국미생물·생명공학회지
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• 제19권3호
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• pp.222-227
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• 1991

Rhizobium fredii USDA193은 대두(Peking)의 근모 세포벽에 침투하여 근류를 형성한다. 본 실험에서는 전보 (1)에서 분리 보고한 R.fredii의 pectate lyase 유전자 clone(SY1)으로부터 $\Omega$변이를 시켰다. 이것을 R.fredii USDA193에 다시 marker-exchange시켜 얻은 변이주(R.fredii USDA193$\Omega$와 R.fredii USDA193omega1)의 pectate lyase 활성이 완전히 block되지 못하였다. R.fredii 내에서는 다른 종류의 pel 유전자가 존재하 것으로 생각되며 pelB 및 pelE의 Rhizobium mutants들은 근류형성 초기단계에서 직접적으로 영향을 미치지 못하였다.

• 한국식물병리학회지
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• 제10권3호
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• pp.163-168
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• 1994

Erwinia rhapontici causes soft-rot disease in a number of plants such as rhubarb, onion, hyacinth and garlic. Pectate lyase (Pel) depolymerizes pectin and other polygalacturonates, which is though to play a role in bacterial invasion of plants. Pel activity was not detected in E. rhapontici cultured in a minimal salts medium containing glycerol, polygalacturonate, or citrus pectin as a carbon source. However, when sterilized potato tuber and Chinese cabbage slices were added to minimal salts polygalacturonate (0.5%) medium, E. rhapontici produced pectate lyase enzyme. Also Pel activity was consistently detected from macerated potato tubers, Chinese cabbage leaves, lettuce leaves and celery petioles tissue. Pel in the extract of macerated Chinese cabbage caused by E. rhapontici strain 1, resulted in electrolyte loss, tissue maceration and cell death of potato tuber tissue. These results indicate that E. rhapontici produces pectate lyase only in the presence of non-diffusible plant components, and that this enzyme probably contributes to its pathogenicity.

• 한국식물병리학회지
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• 제12권1호
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• pp.129-131
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• 1996

Pecatate lyase(Pel)는 펙틴과 펙틴산을 분해하며, 기주식물의 감염에 관여한다. Erwinia rhapontici에 있어서 기주와 병원균이 병원성과의 상호관계를 구명하기 위하여 pectate lyase(Pel) 활성에 미치는 식물체 추출물과 세포벽의 효과를 검토하였다. 본 균은 glycerol이 포함된 minimal salts(MSG) 배지와 식물체 추출물이 첨가된 MSP 배지에서는 Pel 활성이 검출되지 않았다. 그러나 배추, 상추 잎, 감자 괴경, 셀러리 잎자루, 양파 인경, 당근 뿌리의 세포벽이 첨가된 MSP 배지에서는 Pel의 활성이 검출되었다. Pel을 유도하는 식물 인자는 불용성이고, 열처리에 불안전하였다.

• 한국미생물·생명공학회지
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• 제20권6호
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• pp.655-662
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• 1992

알칼리내성 Bacillus sp. Ya-14 유래의 pectate lyase 유전자를 함유한 재조합균주로부터 affinity method, CM-cellose column chromatography와 gel filtration을 통해 효소를 정제하였으며 정제효소의 수율은 10.2, 정제도는 258배였다. 효소의 최적활성 pH는 10.0이었고 pH4.0-10.0까지의 범위에서 안정성이 있었으며, 최적활성온도는 $60^{\circ}C$이고 $50^{\circ}C$까지 열안정성이 있으며, SDS-PASGE에 의해 추정된 분자량은 43KDa 이었다. 아미노산 조정 분석 결과 polar, basic 아미노산의 함량이 높고 특히 Ser, Gly, Tyr의 함량이 높았으며, 정제효소의 N-terminal은 Ala-Asp-Leu-Gly-His-Gln-Thr의 아미노산 서열이었다.

• 한국미생물·생명공학회지
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• 제16권4호
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• pp.316-319
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• 1988

토양으로부터 분리한 알카리내성 Bacillus sp. YA-14의 Pectate lyase(PL) 유전자를 E. coli에 cloning하여 제조한 재조합 plasmid pYPC29는 삽입 된 1.6kb 단편내에 PL 유전자를 함유하고 있었으며, 이 외래 DNA가 Bacillus sp. YA-14의 chromosomal DNA에서 유래된 것임을 Southern hybridization을 통하여 확인하였다. 재조합 plasmid pYPC29는 E. coli내에서 안정하게 존재하였으며 이를 함유한 재조합체의 전체 PL 활성 중 약 70%가 periplasmic space에 존재하였다.

• 한국식물병리학회지
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• 제14권2호
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• pp.125-129
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• 1998

Phytopathogenic bacteria causing soft-rot many vegetables; extracellular enzymes produced by them, pectate lyase(Pel) is important pathogenicity facotrs which cause tissue maceration and cell death. Ten of seventeen plant pathogenic bacteria showed weak Pel activity, four of them showed low Pel activity and Erwinia acrotovora subsp. carotovora, E. chrysanthemi, Pseudomonas marginalis and Xanthomonas campestris pv. campestris showed high Pel activity in the polygalacturonate yeast extract agar (PAY) plate. High Pel activity of the four bacteria species produced the highest Pel activity when pectin or polygalacturonic acid (PGA) was added to minimal salts (MS) medium. Pel activity of the four bacterial species was the highest at 2$0^{\circ}C$ among different temperature conditions. The rate and amount of maceration of potato tuber tissue were highest at 2$0^{\circ}C$ in E. carotovora subsp. carotovora, E. chrysanthemi and P. marginalis, while those were the highest at $25^{\circ}C$ in X. campestris pv. campetris.

• Journal of Microbiology and Biotechnology
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• 제2권4호
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• pp.260-267
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• 1992

Pectate lyase from alkalitolerant Bacillus sp. YA-14 is an endo-type pectate lyase which acts randomly at the $\alpha$-1, 4-galacturonan linkage, and requires calcium or strontium ions for its activity. The enzyme is active on low methyl esterified pectin, but the activity toward a high methyl esterified substrate is reduced. The apparent Km's of the enzyme toward sodium polygalacturonic acid, polygalacturonic acid, and various pectins such as apple pectin, citrus pectin, and genu pectin are 0.826 mg/ml, 0.685 mg/ml, and 1.14 mg/ml, respectively. The enzyme activity is inhibited by SDS, urea, and sodium azide, but not by various reducing reagents, such as $\beta$-mercaptoethanol, Na-thiosulfate, Na-sulfate, cystein, and L-ascorbic acid. The enzyme is inactivated by N-bromosuccinimide, $I_2, H_2O_2$. PMSF, and iodoacetate. Judging from the results of their inhibition types, we speculate that tryptophan and serine residues are directly involved in enzyme activity, while tyrosine and methionine residues are indirectly involved in its activity.

• Journal of Microbiology and Biotechnology
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• 제20권4호
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• pp.670-677
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• 2010

An alkaline pectate lyase, Bsp165PelA, was purified to homogeneity from the culture broth of alkaliphilic Bacillus sp. N16-5. The enzyme showed a specific activity as high as 1,000 U/mg and had optimum activity at pH 11.5 and $50^{\circ}C$. It was composed of a single polypeptide chain with a molecular mass of 42 kDa deduced from SDS-PAGE, and its isoelectric point was around pH 6.0. It could efficiently depolymerize polygalacturonate and pectin. Characterization of product formation revealed unsaturated digalacturonate and trigalacturonate as the main products. The pectate lyase gene (pelA) contained an open reading frame (ORF) of 1,089 bp, encoding a 36-amino acids signal peptide and a mature protein of 326 amino acids with a calculated molecular mass of 35.943 Da. The deduced amino acid sequence from the pelA ORF exhibited significant homology to those of known pectate lyases in polysaccharide lyase family 1. Some conserved active-site amino acids were found in the deduced amino acid sequence of Bsp165PelA. $Ca^{2+}$ was not required for activity on pectic substrates.