• Korean Journal of Microbiology
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• v.55 no.3
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• pp.313-315
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• 2019

An anaerobic bacterial strain WCF-2 was isolated from cow dung in finding cellulose-degrading bacteria for use as silage additives. Strain WCF-2 showed a higher cellulolytic activity than Cellulosilyticum lentocellum DSM $5427^T$, the closest relative of strain WCF-2 (98.2% of 16S rRNA gene sequence similarity). We sequenced the complete genome of strain WCF-2 and compared it with that of C. lentocellum DSM $5427^T$. The OrthoANI value between the two strains was 97.9% thus strain WCF-2 was identified as C. lentocellum. The genome size of strain WCF-2 was 4,779,774 bp with a G + C content of 34.4%, 4,154 coding genes (CDS), 54 pseudo genes, and 142 RNA genes. Strain WCF-2 harbored seven cellulase genes, five of which showed low similarities with those of C. lentocellum DSM $5427^T$.

• Mycobiology
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• v.47 no.1
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• pp.50-58
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• 2019

Agarum clathratum, a brown macroalgae species, has recently become a serious environmental problem on the coasts of Korea. In an effort to solve this problem, fungal diversity associated with decaying A. clathratum was investigated and related ${\beta}$-glucosidase and endoglucanase activities were described. A total of 233 fungal strains were isolated from A. clathratum at 15 sites and identified 89 species based on morphology and a multigene analysis using the internal transcribed spacer region (ITS) and protein-coding genes including actin (act), ${\beta}$-tubulin (benA), calmodulin (CaM), and translation elongation factor (tef1). Acremonium, Corollospora, and Penicillium were the dominant genera, and Acremonium fuci and Corollospora gracilis were the dominant species. Fifty-one species exhibited cellulase activity, with A. fuci, Alfaria terrestris, Hypoxylon perforatum, P. madriti, and Pleosporales sp. Five showing the highest enzyme activities. Further enzyme quantification confirmed that these species had higher cellulase activity than P. crysogenum, a fungal species described in previous studies. This study lays the groundwork for bioremediation using fungi to remove decaying seaweed from populated areas and provides important background for potential industrial applications of environmentally friendly processes.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.31-36
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• 1991

Cellulase genes from thermophilic alkalophilic Bacillus sp. F204 a potent cellulase complex-producing bacterium, were cloned in Escherichia coli with pUC 19. Plasmids pBC191 and pBC192, isolated from transformants forming yellow zone around colony on the LB agar plate containing 0.5% carboxymethyl cellulose and ampicillin, contained 4.6 Kb and 5.8 Kb HindIII fragments, respectively. The 4.6 Kb insert of pBC191 had single sites for BamHI EcoRI, KpnI and pvuII. DNA hybridization and immunodiffusion studies showed that pBC191-encoded cellulase gene was homologous with that of host strain. pKC231, constructed by inserting 4.6 Kb insert of pBC191 at the HindIII site of pKK223-3, E. coli expression vector, and pGC711, constructed by inserting 4.6 Kb insert of pBC191 at the HindIII site of pGR71, E. coli and B. subtilis shuttle vector, had 3.2 times and 2.8 times as much cellulase activity as pBC191, respectively. Substrate specificity analysis showed that cellulases cloned were CMCase.

• Mycobiology
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• v.40 no.2
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• pp.107-110
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• 2012

Genes encoding the cellobiohydrolase enzyme (CBHI), designated as cbhI, were isolated from the basidiomycetes Auricularia fuscosuccinea, Pleurotus giganteus, P. eryngii, P. ostreatus, and P. sajor-caju. Initially, the fungal genomic DNA was extracted using a modified cetyltrimethyl ammonium bromide (CTAB) protocol and used as a DNA template. The cbhI genes were then amplified and cloned using the pGEM-T Easy Vector Systems. The sizes of these PCR amplicons were between 700~800 bp. The DNA sequences obtained were similar showing high identity to the cbhI gene family. These cbhI genes were partial consisting of three coding regions and two introns. The deduced amino acid sequences exhibited significant similarity to those of fungal CBHI enzymes belonging to glycosyl hydrolase family 7.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2005.11a
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• pp.31-31
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• 2005

• The Plant Pathology Journal
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• v.29 no.4
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• pp.364-373
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• 2013

It has been known that most regulation of pathogenicity factor (rpf ) genes in xanthomonads regulates virulence in response to the diffusible signal factor, DSF. Although many rpf genes have been functionally characterized, the function of rpfE is still unknown. We cloned the rpfE gene from a Xanthomonas oryzae pv. oryzae (Xoo) Korean race KACC10859 and generated mutant strains to elucidate the role of RpfE with respect to the rpf system. Through experiments using the rpfE-deficient mutant strain, we found that mutation in rpfE gene in Xoo reduced virulence, swarm motility, and production of virulence factors such as cellulase and extracellular polysaccharide. Disease progress by the rpfE-deficient mutant strain was significantly slowed compared to disease progress by the wild type and the number of the rpfE-deficient mutant strain was lower than that of the wild type in the early phase of infection in the inoculated rice leaf. The rpfE mutant strain was unable to utilize sucrose or xylose as carbon sources efficiently in culture. The mutation in rpfE, however, did not affect DSF synthesis. Our results suggest that the rpfE gene regulates the virulence of Xoo under different nutrient conditions without change of DSF production.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.1
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• pp.40-49
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• 1998

Protoplasts were isolated from mesophyll of tobacco(Nicotiana glauca) transformed with kanamycin-resistant gene (NPT II gene) and potato hairy root callus containing Ri plasmid of Agrobacterium rhiEogenes, and protoplasm fusion was made between the isolated protoplasts. The transgenic tobacco leaf tissue could grow on the media containing high concentrations of kanamycin, but not on the phytohormone-free media. On the other hand, the potato hairy root calli could be cultured on the phytohormone-free media but not on media containing more than 40 ㎍/ml kanamycin. In these conditions, the viability of both protoplasts were above 90%, These selection markers were used for the selection of protoplasts fused between the two, i.e. protoplast fusion was detected using selection media containing 100㎍/ml kanamycin and with no phytohormone. The mixture of 1.0% cellulase, 0.3% macerozyme, and 0.7M mannitol was best for the maximum protoplast production for tobacco, and that of 2.0% cellulase, 2.0% macerozyme, 1.0% dricelase, and 0.5M mannitol for potato. Both tobacco mesophyll and potato callus protoplasts were fused by using PEG solution on the selectable medium. Cell walls were regenerated after 5 days in this medium, and colonies were alive until 4 weeks after cultural, but died after 6 weeks.

• Journal of Microbiology and Biotechnology
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• v.22 no.4
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• pp.462-469
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• 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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.2
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• pp.195-200
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• 1985

This experiment was carried out to know the processes of protoplast isolation, culture and plant regeneration in aims of introducing foreign genes into plant cells through plant gene vector, and cellular selection for plant improvement. The main results indicated that 2% cellulase plus 0.5% macerozyme is proper for isolation of protoplasts from leaf mesophyll cells of N. plumbaginifolia, plating efficiency was higher in 1.4-2.0 x 10$^4$ cells/ml, complete cell wall was regenerated after 2 days culture, cell division and cell mass were observed after 4 days and 2 weeks, respectively, colony was developed after 3 weeks culture, addition of 1-2mg/l BA promoted shoot differentiation while root differentiation did not required hormone and seeds were harvested from more than 100 cell lines for further investigation and study.

• Korean Journal of Microbiology
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• v.55 no.2
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• pp.160-163
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• 2019

Senegalimassilia sp. KGMB 04484 was isolated from fecal samples obtained from a healthy Korean. The whole-genome sequence of Senegalimassilia sp. KGMB 04484 was analyzed using the PacBio Sequel platform. The genome comprises a 2,748,041 bp chromosome with a G+C content of 61.18%, 2,300 total genes, 2,139 protein-coding gene, 21 rRNA genes, and 51 tRNA genes. Also, we found that strain KGMB 04484 had some genes for hydrolysis enzyme, fatty acid biosynthesis and metabolism in its genome based on the result of genome analysis. Those genes of KGMB 04484 may be related to regulation of human health and digest.