• 한국미생물·생명공학회지
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• 제24권5호
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• pp.560-566
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• 1996

A strain capable of producing thermostable chitinase suitable for chitooligosaccharide production was isolated from high temperature environment and identified as Bacillus licheniformis. The chitinase from Bacillus licheniformis KFB-Cl4 was only induced by addition of colloidal thitin into the basal medium as carbon source, showing the decrease of the chitinase production by supplernental addition of other carbon sources into the medium containing 1.0% colloidal chitin. Among organic and inorganic nitrogen sources, yeast extract was the most effective for the increase of total activity and specific activity, and had high affinity for the enzyme production. The optimum temperature of cell growth and thermostable chitinase production was 55$\circ$C. The optimum culture medium was composed of 1.2% colloidal chitin, 0.15% K$_{2}$HPO$_{4}$, 0.05% KH$_{2}$PO$_{4}$, 0.01% MgSO$_{4}$-7H$_{2}$O, 0.1% yeast extract (pH 6.5). Bacillus licheniformis KFB-C14 produced the thermostable chitinase of 3.89 units per ml culture fluid and 7.4 units per mg protein under rotary shaking at 150 rpm for 40 hr.

• 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.

• Applied Biological Chemistry
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• 제36권5호
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• pp.370-375
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• 1993

벼잎의 산성 buffer(pH 2.8) 추출 조효소는 5개의 전기영동 band들이 PR protein으로 알려진 chitinase와 ${\beta}-1,3-glucanase$의 효소활성을 보유하고 있는 것으로 나타났다. 조효소는 DEAE-cellulose 및 chitin affinity chromatography로 염기성 및 산성 효소군으로 분획되었으며, 이들은 두 효소활성이외에도 lysozyme 활성을 보유하고 있었다. 분자량이 $14.3{\sim}66.0\;kd$ 범위인 이 두 효소군이 보유한 각 효소활성의 최적 pH와 온도를 조사해본 결과,${\beta}-1,3-glucanase$는 각각 pH 5와 $60^{\circ}C$로 동일하였으나, chitinase는 염기성 효소군에서 pH 4와 $50^{\circ}C$, 산성 효소군에서는 pH 3와 $60^{\circ}C$으로 다르게 나타나서, 전기영동 양상과 더불어 서로 상이한 효소분획인 것으로 추정되었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제4권1호
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• pp.26-31
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• 1999

The advantages of the organism Streptomycs griseus HUT 6037 is that the chitinase and chitosanase using chitinaceouse substrate are capable of hydrolyzing both amorphous and crystalline chitin and chitosan. We attempted to investigate the optimization of induction protocol for high-level production and secretion of chitosanase and the influence of chitin and partially deacetylated chitosan sources (75∼99% deacetylation). The maximum specific activity or chitinase has been found at 5 days cultivation with the 48 hours induction time using colloidal chitin as a carbon source. To investigate characteristic of chitosan activity according to substrate, we used chitosan with various degree of deacetylation as a carbon source and found that this strain accumulates chitosanase in the culture medium using chitosanaceous substrates rather than chitinaceous substrates. The highest chitosanase activity was also presented on 4 days with 99% deacetylated chitosan. The partially 53% deacetylated chitosan can secrete both chitinase and chitosanase which was defined as a soluble chitosan. The specific activities of chitinase and chitosanase were 0.89 at 3 days and 1.33 U/mg protein at 5 days, respectively. It indicate that chitosanase obtained from S. griseus HUT 6037 can hydrolyze GlcNAc-GlcN and GlcN-GlcN linkages by exo-splitting manner. This activity increased with increasing degree of deacetylation of chitosan. It is the first attempted to investigate the effects of chitosanase on various degrees of deacetylations of chitosan by S. griseus HUT 6037. The highest specific activity of chitosanase was obtained with 99% deacetylated chitosan.

• BMB Reports
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• 제32권6호
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• pp.541-546
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• 1999

When we compared the chitinase activity of various plant sources using colorimetric or active gel-staining assay methods, the specific activity of pumpkin leaves was the highest among the samples we analyzed. The highly active chitinase from pumpkin leaves (designated PL-ChtIII) was purified to homogeneity using affinity chitin gel and HPLC Mono-Q anion-exchange cloumn chromatographies. In contrast to other members of the class III chitinase family, PL-ChtIII showed a strong binding affinity to the regenerated chitin gel column. The apparent molecular weight of PL-ChtIII was estimated to be 29 kDa on SDS-PAGE gel, while its optimum pH and temperature were shown to be pH 6.0 and $60^{\circ}C$, respectively. Analyzing the reaction products of PL-ChtIII with swollen chitin as substrate, the dimer and tetramer of N-acetylglucosamine were produced as major products in the first hour of the enzymatic reaction along with a small amount of monomers and trimers. As the reaction time increased, dimeric N-acetylglucosamine became the predominant form of reaction product.

• The Plant Pathology Journal
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• 제22권2호
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• pp.107-114
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• 2006

The white cottony stem rot pathogen Sclerotinia scierotiorum was subjected to 70 different isolates of actinomycetes indigenous to Jordan as biological control agents. Forty of them demonstrated chitinase activity on crab shell chitin agay (CCA) media and they were segregated into three groups: 14 highly active, 12 moderately active, and 14 with low activity, with average clearing zones of (4.7-8.3), (3.7-4.3), and (2.3-3.3) mm surrounding colonies on CCA, respectively. Further, these isolates were able to inhibit radial mycelium growth of the pathogen and were categorized into three antagonistic groups: 13 strong, 13 moderate, and 14 weak antagonists, with antibiosis inhibition Bones of (32.0-45.7), (22.7-31.3), and (3.7-22.3) mm, respectively. High levels of chitinase activity of the isolates Ma3 (8.3 mm), Jul (7.7 mm), and Sa8 (7.7 mm) with their antagonistic activity against mycelium growth of 45.7, 44.3, and 40.7 mm were observed, respectively. These isolates exhibited fungicidal activity against sclevotia of S. sclerotiorum. On the other hand, isolates Na5, Aj3, and Aj2 that produced no chitinase showed fungistatic effect only.

• 미생물학회지
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• 제38권4호
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• pp.224-224
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• 2002

Chitin-degrading marine bacterial strain 98CJ11027 was isolated from bryozoa from the coastal area of Cheju Island, Korea, and identified as a member of the genus Vibrio. The molecular mass of the main extracellular chitinase (chitinase I), purified from strain 98CJ11027, was estimated to be 98 kDa. The optimal condition for chitinase I activity is pH 6.0 and 45℃. The activity was inhibited by $Fe^+2$ and$Cu^+2$. Chitinase I displayed the hydrolysis type of chitobiosidase and catalyzed reversed hydrolysis leading to the synthesis of tetraacetylchitotetraose.

• 한국미생물·생명공학회지
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• 제18권4호
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• pp.437-441
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• 1990

근채류 식물의 근부원인이 되는 식물병원균 Fusarium solani의 생육을 강력히 길항하는 생물반제균 Pseudomonas stutzeri YPL-1을 모균주로 하여 UV나 NTG로 돌연변이시킴으로써 길항능이 증강된 강력한 생물방제균을 유전적으로 육종하고자 하였다. 그 결과 길항기작의 원인인 외막가수분해효소 chitinase 생산능이 2.5배, 2.0배 정도로 증강된, 동시에 길항능도 모균주에 비해 1.7배, 1.5배 정도로 비례해서 증강된, 강력한 우수 길항변이주 P.stutzeri YPL-M26(UV)과 P.stutzeri YPL-M178(NTG)을 유전적으로 육종할 수 있었다. 길항종강변이주에 의한 F.solani의 생육억제기작도 모균주에서와 같이 고분자 물질인 chitinase를 주로 하는 외막가수분해효소에 의한 것으로 확인되었고, 균사신장억제율도 조사해 본 결과 조효소액 첨가 경우 24시간째에는 모균주 경우 87.1 정도인데 비해 거의 100의 생육억제율을 나타내는 강력한 생물반제균으로 유전적 육종을 할 수 있었다. 한편 변이주와 모균주의 효소에서도 그 최적반응 pH등 각종 효소학적 특성이 동일하였다.

• 식물조직배양학회지
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• 제21권6호
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• pp.357-362
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• 1994

키틴 가수분해 효소와 베타-1,3-글루카네이즈는 식물체의 주요 방어효소로 여겨지고 있다. 본 논문에서는 아기장대풀의 잎조직으로부터 고정된 현탁배양주를 만들고 이어서 에틸렌과 유인제 (elicitor) 처리에 의한 키틴 가수분해 효소유도양상을 분석하였다. 키틴 가수분해 효소활성은 $^3$H으로 표지된 키토산을 기질로 한 radiochemical 분석방법이나 담배식물체의 키틴 가수분해 효소를 대상으로 얻어진 항체를 이용하여 Western 분석방법을 사용하였다. 이 결과 에틸렌과 유인제 처리 공히 48시간후에 가장 활성이 높게 나타남을 관찰하였다. 또한 씨앗, 새싹, 식물체의 잎, 뿌리 등에서의 활성을 조사하여 뿌리에서 키틴 가수분해 효소 활성이 높음을 확인하였다.

• Fisheries and Aquatic Sciences
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• 제6권1호
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• pp.7-12
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• 2003

Chitinase and chitobiase produced by Aeromonas sp. J-5003 were purified and characterized. The chitinase was purified to 19.4 folds by gel chromatography and ion-exchange chromatography with the overall yield of $2.2\%$ and the specific activity of 93.1 unit/mg. The purified enzyme showed a single band on SDS-PAGE with MW 54kDa. The optimum pH and temperature of the purified chitinase were 7.0 and $37^{\circ}C$, respectively, and this enzyme stable in the range of pH 6.0 to 10.0 below $37^{\circ}C$. $Mg^{2+},\;Ca^{2+}\;and\;Na^+$ slightly stimulated the chitinase activity. However, $Hg^{2+}\;and\;Fe^{3+}$ inhibited chitinase activity. The chitobiase was purified by Sephacryl HR-l00 gel chromatography and DEAE-Sephadex A-50 ion-exchange chromatography with 33.5 purification folds and $4.3\%$ yield. The purified enzyme showed a single band with MW 63 kDa. The optimum pH and temperature of the purified chitobiase were 7.0 and $37^{\circ}C$, respectively. And this enzyme was stable in the range of pH 6.0 to 9.0 and at the temperature below $37^{\circ}C$. The enzyme activity was increased by $Mn^{2+}$, but it was inhibited by $Ag^+$.