• Journal of Microbiology and Biotechnology
• /
• 제22권4호
• /
• pp.462-469
• /
• 2012

A metagenomic fosmid library was constructed from genomic DNA isolated from the microbial community residing in hindguts of a wood-feeding higher termite (Microcerotermes sp.) collected in Thailand. The library was screened for clones expressing lignocellulolytic activities. Fourteen independent active clones (2 cellulases and 12 xylanases) were obtained by functional screening at pH 10.0. Analysis of shotgun-cloning and pyrosequencing data revealed six ORFs, which shared less than 59% identity and 73% similarity of their amino acid sequences with known cellulases and xylanases. Conserved domain analysis of these ORFs revealed a cellulase belonging to the glycoside hydrolase family 5, whereas the other five xylanases showed significant identity to diverse families including families 8, 10, and 11. Interestingly, one fosmid clone was isolated carrying three contiguous xylanase genes that may comprise a xylanosome operon. The enzymes with the highest activities at alkaline pH from the initial activity screening were characterized biochemically. These enzymes showed a broad range of enzyme activities from pH 5.0 to 10.0, with pH optimal of 8.0 retaining more than 70% of their respective activities at pH 9.0. The optimal temperatures of these enzymes ranged from $50^{\circ}C$ to $55^{\circ}C$. This study provides evidence for the diversity and function of lignocellulose-degrading enzymes in the termite gut microbial community, which could be of potential use for industrial processes such as pulp biobleaching and denim biostoning.

• 한국균학회지
• /
• 제24권3호통권78호
• /
• pp.206-213
• /
• 1996

Talaromyces luteus 6112 균주에 돌연변이원 N-methyl-N'-nitro-N-nitrosoguanidine을 처리하여 고온성 돌연변이주인 T. luteus 2004를 선별하였다. T. luteus 2004 균주는 고온성 섬유소 분해 효소인 carboxymethylcellulase(CMCase)와 그 외의 다당류 분해효소인 avicellase, xylanase, ${\beta}-glucosidase$ 등을 생성하였다. 고온성 섬유소 분해효소의 생성은 3% carboxymethylcellulose(CMC) 최소배지에서 가장 높게 유도되었으므로 CMC가 CMCase 생성의 유도물질임을 알 수 있었다. 고온성 섬유소분해효소의 생성에 있어서 포도당과 D-cellobiose는 CMCase 생성에 catabolite repressor로 작용함을 보여 주었다. T. luteus 2004의 섬유소 분해효소의 효소학적 특성은 $70^{\circ}C$, pH 4에서 최고의 활성을 보여주는 고온성 효소이므로 대체에너지 개발에 활용 가능한 균주로 사료된다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제18권10호
• /
• pp.1435-1439
• /
• 2005

Bacterio-mineral water (BMW) produced from manure has been known to exert a number of positive effects on animal production and odor control. An experiment was conducted to examine the effects of BMW produced from bio-reacted swine manure on in vitro gas production, cellulose degradation, microbial growth and fibrolytic enzyme activities of mixed rumen microorganisms. The five levels of 0, 0.001, 0.005, 0.01 and 1.0% BMW were supplemented into serum vials containing mixed rumen microorganisms. Incubations were carried out anaerobically at $39^{\circ}C$ without shaking for 0, 12, 24, 48, 72 and 96 h. There were no significant (p>0.05) differences among the treatments for the initial rate of gas production. At 72 h incubation, the gas production tended (p<0.1) to be increased by the 0.01 and 1.0% BMW treatments compared with control and the 0.001% BMW treatment. At the end of incubation (96 h), the sample supplemented with 0.01% BMW was higher (p<0.05) than control (0% BMW) in the gas production. The microbial growth rate was increased by all the BMW treatments, while 0.01% BMW was most effective in stimulating the growth rate. Although the addition of BMW on the filter paper DM degradation was not significantly influenced throughout the incubation period except the 48 h incubation, DM degradation tended to be increased by all BMW treatments compared with control. The addition of both 0.005 and 0.01% BMW highly increased (p<0.05) CMCase activity compared with control after 24 h and 48 h incubation, while at the 72 h incubation the 0.01% BMW addition only significantly increased (p<0.05). After 72 h incubation, the xylanase activity was significantly (p<0.05) increased with the addition of 1.0% BMW compared with the addition of 0.001 and 0.005% BMW, while at the other incubation times, the xylanase activity was not different among the treatments. In conclusion, the 0.01% BMW of supplementation level would be the suitable addition level to stimulate rumen fermentation increasing microbial growth and cellulose degradation.

• Journal of Animal Science and Technology
• /
• 제45권5호
• /
• pp.805-812
• /
• 2003

본 시험은 유형이 서로 다른 세 가지 형태의 TMR을 반추위에 누관이 장착된 면양을 이용하여 3${\times}$3 라틴 방각법으로 반추위내 발효성상, 효소역가 및 전장 소화율을 조사하였다. 시험 결과를 살펴보면, 전반적으로 반추위 내 pH, 암모니아태 질소 농도, 총 VFA, 각종 VFA생성량, A/P ratio 및 각종 효소(CMCase, Xylanase 및 Protease) 역가는 건TMR를 급여했을 때와 비교하여 습TMR과 발효TMR급여 시 높은 경향을 보였다. 또한 건물, 유기물, 조단백질, 조지방, NDF 및 ADF의 전장 소화율도 건TMR 급여 시 보다 습TMR과 발효TMR를 급여했을 때 높게 향상된 것을 볼 수 있다. 따라서 본 시험의 결과들을 종합해 보면 보다 안정적이고 활발한 반추위 발효과정과 영양소 이용효율 측면에서 건TMR보다 습TMR이나 발효TMR이 우수한 것으로 요약할 수 있다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제27권2호
• /
• pp.290-301
• /
• 2014

The first purpose of this review is to outline some of the background information necessary to understand the mechanisms of action of fibre-degrading enzymes in non-ruminants. Secondly, the well-known and understood mechanisms are described, i) eliminating the nutrient encapsulating effect of the cell wall and ii) ameliorating viscosity problems associated with certain Non Starch Polysaccharides, particularly arabinoxylans and ${\beta}$-glucans. A third, indirect mechanism is then discussed: the activity of such enzymes in producing prebiotic oligosaccharides and promoting beneficial cecal fermentation. The literature contains a wealth of information on various non starch polysaccharide degrading enzyme (NSPase) preparations and this review aims to conclude by discussing this body of work, with reference to the above mechanisms. It is suggested that the way in which multi- versus single-component products are compared is often flawed and that some continuity should be employed in methods and terminology.

• Journal of Animal Science and Technology
• /
• 제57권7호
• /
• pp.23.1-23.6
• /
• 2015

Cellulose degrading bacteria from koala faeces were isolated using caboxymethylcellulose-Congo red agar, screened in vitro for different hydrolytic enzyme activities and phylogenetically characterized using molecular tools. Bacillus sp. and Pseudomonas sp. were the most prominent bacteria from koala faeces. The isolates demonstrated good xylanase, amylase, lipase, protease, tannase and lignin peroxidase activities apart from endoglucanase activity. Furthermore many isolates grew in the presence of phenanthrene, indicating their probable application for bioremediation. Potential isolates can be exploited further for industrial enzyme production or in bioremediation of contaminated sites.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
• /
• pp.225-228
• /
• 2008

This study shows that lignocellulosic biomass saccharification work has been carried out with rice-straw by the extracellular enzyme from KMU001, and the enzymes produced in 5%(w/v) wood biomass were characterized by protein and various enzyme activity measurements. Several cellulases such as Endoglucanase(EG), $\beta$-D-1,4-Glucosidase(BGL), Cellobiohydrolase(CBH), and $\beta$-D-1,4-Xylanase (BXL) were detected. Saccharification of rice-straw by the enzyme yielded about 233mg/g of glucose after 48hrs.

• Journal of Microbiology and Biotechnology
• /
• 제2권1호
• /
• pp.7-13
• /
• 1992

A moderately thermophilic, alkalophlic and powerful crystalline cellulose-digesting bacterium, Bacillus K-12, was isolated from filter paper wastes and found to be similar to Bacillus circulans or Bacillus pumilis, except for its ability to grow at a moderately high pH and temperature. The isolate grew at a pH ranging from 6 to 10 and at a temperature ranging from 35 to $65^{\circ}C$ and produced a large amount of cellulase components containing avicelase, xylanase, CMCase, and FPase when grown in avicel medium for 5 to 7 days at $50^{\circ}C$. The crude enzyme preparation from the culture broth hydrolyzed xylan, raw starch, pullulan and ${\beta}-1,3$ glucan such as laminarin. Furthermore, the enzyme hydrolyzed crystalline cellulose to cellobiose and glucose and had a broad pH activity curve (pH 6~9). The enzyme was stable up to $70^{\circ}C$.

• Journal of Animal Science and Technology
• /
• 제63권3호
• /
• pp.666-670
• /
• 2021

Paenibacillus konkukensis sp. nov., SK3146 is a novel strain isolated from a pig feed. Here, we present complete genome sequence of SK3146. The genome consists of a single circular genome measuring 7,968,964 bp in size with an average guanine + cytosine (G+C) content of 53.4%. Genomic annotation revealed that the strain encodes 151 proteins related to hydrolases (EC3), which was higher than those in Bacillus subtilis and Escherichia coli. Diverse kinds of hydrolases including galactosidase, glucosidase, cellulase, lipase, xylanase, and protease were found in the genome of SK3146, coupled with one bacteriocin encoding gene. The complete genome sequence of P. konkukensis SK3146 indicates the immense probiotic potential of the strain with nutrient digestibility and antimicrobial activity functions.

• 미생물학회지
• /
• 제29권1호
• /
• pp.8-15
• /
• 1991

Interspecific hybrids between the ASpergillus spp., A. awamori, A. usamii and A. oryzae, were obtained by nuclear transfer technique. Nuclei isolated from an auxotrophic mutant strain were transferred into the protoplasts of a recipient strain of different species. The frequency of interspecific hybrid formation by nuclear transfer was $2*10^{-5}$ $-7*10^{-4}$ In contrast, no interspecific hybrid was isolated by protoplast fusion. Among the hybrids tested, 10 strains showed increased activity of some or all components of cellulases, xylanases and amylase up to more than two times. Isozyme pattern of the hybrids were analyzed by polyacrylamide gel electrophoresis and isoelectric focusing followed by activity staining, which showed that some of the hybrids have isozyme patterns unidentical to either of the two parents. By measuring the DNA contents and the sizes ofthe conidia, the karyotypes of the hybrids were estimated to be aneuploid near to haploid, diploid or triploid. It was concluded that the unclear transfer technique is much more efficient in the formation of interspecific hybrids than protoplast fusion and is very useful for the improvement of Aspergillus strains.