• 한국어병학회지
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• 제6권2호
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• pp.103-110
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• 1993

Sau3AI으로 부분절단한 Serratia marcescens genomic DNA(5Kb 이상)을 pUC19의 BamHI site에 삽입하여 total genomic library를 준비하였다. Swollen colloidal chitin media에서 halo를 형성하는 2개의 E.coli 형질전환주를 선별하였다. 이들 colony가 chitinase 유전자를 갖음을 재확인하기 위하여 4-methylumbelliferyl N-acetyl-$\beta$-D-glucosaminide(4-MuFGlcNAc)를 이용하였다. 4-MuFGlcNAc는 chitinase에 대한 기질특이성을 나타내며 형광을 나타내는 기질로서 positive clone들은 360nm의 자외선을 조사하였을 경우 밝은 형광을 나타낸다. pUC19으로 부터 유래된 2 종류의 다른 chitinase clone, pCH1(11.0Kb) 및 pCH2(7.5Kb)를 genomic DNA library로 부터 분리하였으며, 이들의 제한효소지도를 작성한 결과 서로 다른 제한효소지도를 나타내었다. pCH1EA 및 pCH2로 부터 각각의 EcoRI-Xbal fragment를 subcloning함으로써 두개의 다른 chitinase 유전자의 위치를 결정하였다. pCH1EA 및 pCH2를 cross hybridization 한 결과 hybridization signal을 나타내지 않아 서로 유사성이 없는 것으로 사료된다.

• 한국미생물·생명공학회지
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• 제7권3호
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• pp.149-155
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• 1979

자연계에서 진균류와 절족동물의 외피를 이루는 주된 다당류인 chitin(N-acetyl glucosamine polymer)의 $\beta$-1, 4-lingkage를 가수분해하는 Strepto-myces sp. 115-5 균주로부터 생성되는 chitinase를 정제하여 그 성질을 조사하였다. 48시간 진탕배양하여 생성된 chitinase를 ammonium sulfate처리, 1차 Sephadex G-100, DEAE-Cellulose, 2차 Sephadex G-100 column chromatography하여 정제하였으며 그 순도를 CM-Sephadex C-50 column chromatography 및 polyacryla-mide gel electrophoresis로서 확인하였다. 이 chitinase는 chitin과 chitosan을 가수분해 할수 있었으나 cellulose는 분해할수 없었고 chitin을 기질로서 사용하였을 경우 Km value가 3.6mg/ml이며 Vmax가 100 $\mu$mole/hr였다. Activation energy는 산 가수분해보다 훨씬 낮은 3.66kca1/mole이었고 분자량은 Sephadex G-100을 사용한 column chromatography에서 56,000 daltons으로 나타났으며, 이 chitinase의 등전점은 pH3.0에서 보여졌다.

• Applied Biological Chemistry
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• 제37권1호
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• pp.49-55
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• 1994

벼잎의 산성용액 추출물로부터 ion exchange chromatography chitin affinity chromatography chromatofocusing gel slicing 등의 방법으로 단백질 RCG-2를 순수분리하였다. 본 단백질은 chitin과 laminarin을 가수분해하므로 chitinase와 ${\beta}-1,3-glucanase$ 활성을 함께 보유하고 있는 것으로 나타났으며, 이외에도 M. lysodeiktikus cell wall을 가수분해하는 lysozyme 활성도 보유하는 것으로 판명되었다. 분자량이 29.77 kd인 본 효소의 chitinase 활성은 pH 4.0에서, ${\beta}-1,3-glucanase$ 활성은 pH 7.0에서 최대로 나타났고, 최적온도는 두 효소 활성 모두 $40^{\circ}C$ 이었다. chitin에 대한 $K_M$ 값은 7.86 mM, $V_{max}$는 $0.025\;{\mu}M/min$, laminarin $({\beta}-1,3-glucan)$에 대한 것은 각각 5.95 mM, $0.16{\mu}\;M/min.$ 이었으며, 정제된 효소는 chitin을 chitooligosaccharide로 분해하는 것으로 나타나서 endochitinase로 판명되었다.

• The Plant Pathology Journal
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• 제21권3호
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• pp.275-282
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• 2005

A chitinolytic bacterium, Chromobacterium sp. strain C-61, was found strongly antagonistic to Rhizoctonia solani, a causal agent of damping-off of eggplant. In this study, the biocontrol activity and enzymatic characteristics of strain C-61 were compared with its four Tn5 insertion mutants (C61-A, -B, -C, and -D) that had lower chitinolytic ability. The chitinase activity of a 2-day old culture was about $76\%,\;49\%\;and\;6\%$ level in C61-A, C61-B and in C61-C, respectively, compared with that of strain C-61. The $\beta-N-acetylhexosaminidase$(Nahase) activity was little detected in strain C-61 but increased largely in C-61A, C61-B and C61-C. Activities of chitinase and Nahase appeared to be negatively correlated in these strains. Another mutant, C-61D, produced no detectable extracellular chitinase and Nahase. The in vitro and in vivo biocontrol activities of strain C-61 and its mutants were closely related to their ability to produce chitinase but not Nahase. No significant differences in population densities between strain C-61 and its mutants were observed in soil around eggplant roots. The results of SDS-PAGE and isoelectrofocusing showed that a major chitinase of strain C-61 is 54-kDa with pI of approximately 8.5. This study provides evidence that the biocontrol activity of Chromobacterium sp. strain C-61 against Rhizoctonia solani depends on the ability to produce chitinase with molecular weight of 54-kDa and pI of 8.5.

• 미생물학회지
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• 제27권1호
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• pp.56-62
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• 1989

Chitin 분해 활성이 높은 Streptomyces 균주들을 인삼재배 토양에서 분리하고, 그 균주들이 인상뿌리 썩음 병균인 Fµsarium solani 에 미치는 길항효과와 그 작용을 조사하였다. 분리된 Streptomyces 중 몇 균주는 F. solani 의 포자발아와 발 아판의 생장을 억제하였고 균사를 분해하였으며, 동시에 세포벽 분해효소로 알려친 Chitinase를 생산하였다. 그중에서도 S alboniger ST 59 와 S. roseolilacinus ST 129 는 길항효과가 아주 좋았는데, 병원균의 분생포자를 두 Streptomyces 의 농축배 양여액에 14일간 처리하였을 때 포지숫자가 처음 정종 정도의 20%로 줄어을였다. 특히 S. alboniger ST 59는 뱅균인 F solani의 분생포자, 균사 뿐만 아니라 분해되기 어려운 후막포자까지도 분해하였다. 이것으로 비푸어 보건데, F. solani의 이 Streptomycetes에 의한 억제작용은 항생물질에 영향을 받은 병균이 Chitinase에 의해 분해된 것으로 생각된다.

• 생명과학회지
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• 제9권4호
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• pp.341-347
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• 1999

Insects use chitinolytic enzyme to digest chitin in the exoskelton during the molting process. We have isolated and sequenced a chitinase-encoding cDNA from the silkworm, Bombyx mandarina, compared its sequenced with genes encoding chitinolytic enzymes from other sources. The insert DNA in the clone is 2,675 nucleotides long with an open reading frame of 1,695 uncletides that encodes a protein of 565 amino acids with a molecuar weight of 63.4 kDa. The 3' -untranslated region of 889 nucleotides is AT-rich and contains two putative polyadenylation signals. The N-terminal sequence of the encoded protein contains numerous hydrophobic residues characteristic of a leader peptide. The amino acid alignment revealed that the endo-$\beta$-N-acetylglucosaminidase had 83% and 97% homology with M. sexta and B. mori, respectively. The deduced amino acid had two highly conserved region at the amino acid residues 97-111 and 139-148 that were related to the existing chitinase.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1986년도 추계학술대회
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• pp.522.3-523
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• 1986

A Screening test was carried out for chitin-decomposing bacteria. In 100 samples from soil, fesh water and sea water, 7 strains of Chitinolytic bacteria were isolated. 5-3K which exhibited the highest chitinase activity was identified as Aeromonas hydrophila and cultural conditions from maximum chitinase production were determined. Optimum Chitinase production was obtained at pH 7, 33eC and with chitin concentration greater tham 0.2% Under optimal conditions, high yields of Chitinase were obtained in 16-30 hours. Chitinase was purified by ammonium sulfate precipitation and sephadex G-100 gel-filtration from the culture filtrgte.

• 한국미생물·생명공학회지
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• 제27권5호
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• pp.349-353
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• 1999

Antagonistic Promicromonospora sp. KH-28 isolated from a suppressive soil could produced a chitinase and a antifungal antibiotic for the biocontrol ability. The chitinase and the antibiotic appeared to inhibit plant pathogens of Fusarium oxysporum. Phytophthora capsici, Alternaria kiki, fusarium solani, Stemphylium sp., and Psudomonas fluorescens. the antibiotic produced from the strain was identified as a antifungal substance of 503 dalton having a pyrimidine skeleton with an aliphatic side chain. The Promicromonospora sp. KH-28 was able to suppress effectively F. oxysporum derived-fusarium wilt of red-pepper plant in the pot in vivo test.

• Archives of Pharmacal Research
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• 제14권3호
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• pp.255-260
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• 1991

Chitinase was partially purified from Allium fistulosum L (green onion_. Protein fraction precipitated from ammonium sulfate was passed through CM-Sepharose and Sephacryl HR-200. The specific activity of the chitinase was 6.4 units/mg and total recovery was 6.3%. The analysis of the products from the digestion of N-acetychitohexaose indicated that chitinase was endo in action, with oligerms from N-acetylchitobiose to chitotetraose. N-Acetylglucosaminidase from the same species hydrolyzed oligomers obtained from chitinase reaction to lower oligosaccharides. These data demonstrated that chitinolytic system exists in green onion.

• 한국미생물·생명공학회지
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• 제47권1호
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• pp.96-104
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• 2019

Beauveria bassiana, one of the most common entomopathogenic fungi, has been isolated, pre defined and characterized in-house from soil of tea cultivation area. Experiments have been performed to verify the presence of chitinase as intracellular metabolite and its release as extracellular product rendering the spores with biopesticide activity. Although there are many responsible enzymes for the pest killer action of B. bassiana, binding property of chitinase depending on presence as well as absence of serine supplemented in the media has been studied with respect to the production and kinetics. A programmed investigation conclusively indicates that the isolated spore (hyphae) of B. bassiana has been metabolically enriched with the enzyme chitinase in presence of an externally added amino acid serine with its inhibitory kinetics.