• Journal of Microbiology and Biotechnology
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• v.24 no.8
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• pp.1073-1080
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• 2014

A total of 10 cellulase-producing bacteria were isolated from soil samples irrigated with paper and pulp mill effluents. The sequencing of 16S rRNA gene revealed that all isolates belonged to different species of genus Bacillus. Among the different isolates, B. subtilis IARI-SP-1 exhibited a high degree of ${\beta}$-1,4-endoglucanase (2.5 IU/ml), ${\beta}$-1,4-exoglucanase (0.8 IU/ml), and ${\beta}$-glucosidase (0.084 IU/ml) activity, followed by B. amyloliquefaciens IARI-SP-2. CMC was found to be the best carbon source for production of endo/exoglucanase and ${\beta}$-glucosidase. The ${\beta}$-1,4-endoglucanase gene was amplified from all isolates and their deduced amino acid sequences belonged to glycosyl hydrolase family 5. Among the domains of different isolates, the catalytic domains exhibited the highest homology of 93.7%, whereas the regions of signal, leader, linker, and carbohydrate-binding domain indicated low homology (73-74%). These variations in sequence homology are significant and could contribute to the structure and function of the enzyme.

• Journal of Microbiology and Biotechnology
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• v.24 no.12
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• pp.1699-1706
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• 2014

A lichenase gene (mt-lic) was identified for the first time through function-based screening of a soil metagenomic library. Its deduced amino acid sequence exhibited a high degree of homology with endo-${\beta}$-1,3-1,4-glucanase (having both lichenase and chitosanase activities), encoded by the bgc gene of Bacillus circulans WL-12. The recombinant lichenase overexpressed and purified from Escherichia coli was able to efficiently hydrolyze both barley ${\beta}$-glucan and lichenan. The enzyme showed maximal activity at a pH of 6.0 at $50^{\circ}C$, with Azo-barley-glucan as the substrate. The metal ions $Mn^{2+}$, $Mg^{2+}$, $Ca^{2+}$, and $Fe^{2+}$ enhanced the enzymatic activity, whereas the $Cu^{2+}$ and $Zn^{2+}$ ions inhibited the enzymatic activity. The $K_m$ and $V_{max}$ values of the purified lichenase were determined to be 0.45 mg/ml and 24.83 U/min/mg of protein, respectively.

• Korean Journal of Plant Resources
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• v.23 no.6
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• pp.535-540
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• 2010

Phenylalanine ammonia-lyase (PAL), a key enzyme of the phenylpropanoid biosynthesis pathway, is activated by a number of developmental and environmental cues. The coding region of the NtPAL4 gene was 2,154 bp in length, and its deduced protein was composed of 717 amino acids. Sequence analysis of NtPAL4 cDNA from tobacco (Nicotiana tabacum L.) revealed high structural similarity to PAL genes of other plant species. The NtPAL4 gene exists as a single copy in the tobacco plant, and its transcripts were strongly expressed in flowers and leaves. NtPAL4 expression was significantly induced in response to NaCl, mannitol, and cold treatments, but it was not induced by abscisic acid (ABA). NtPAL4 expression decreased gradually after treatment with ABA and $H_2O_2$; however, NtPAL4 transcripts accumulated after treatment with methyl viologen (MV). Our results suggest that the NtPAL4 gene may function in response to abiotic stresses.

• Journal of fish pathology
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• v.25 no.1
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• pp.11-20
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• 2012

C-type lectins are crucial for pathogen recognition, innate immunity, and cell-cell interactions. In this study, a C-type lectin gene was cloned from the rock bream. The full-length RbCTL cDNA was 729 bp with a 429 bp ORF encoding a 164-residue protein. The deduced amino acid sequence of RbCTL had all of the conserved features crucial for its fundamental structure, including the four cysteine residues involved in sulfide bridge formation and potential $Ca^2+$/carbohydrate-binding sites. RbCTL contains a signal peptide one single carbohydrate recognition domain. It showed 29.4% similarity to the C-type lectin of rainbow trout. RbCTL mRNA was predominately expressed in gill and head-kidney tissue and expressed less in peripheral blood leukocytes, trunk-kidney, spleen, liver, intestine and muscle. Expression of RbCTL was differentially upregulated in rock bream stimulated with LPS, Con A/PMA and poly I:C.

• ALGAE
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• v.22 no.2
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• pp.131-139
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• 2007

The expression of genes responding to cold stress in a freshwater alga, Spirogyra varians, was studied by using differential expression gene (DEG) method. A gene strongly up-regulated in 4°C was isolated and designated as SVCR2 (Spirogyra varians cold regulated) gene. The cDNA encoding SVCR2 was cloned using λZAP cDNA library of Spirogyra varians. The deduced amino acid had a sequence similarity with trans-membrane protein in Arabidopsis thaliana (Q9M2D2, 52.7%). Northern blot analysis demonstrated that transcript level of SVCR2 increased about 10 fold under low temperature (4°C), compared with that cultured at warm (20°C) conditions. The expression of SVCR2 was also affected by light conditions. When the plants were exposed to high light (HL) (1200 μmol photon m–2 s–1), the expression of SVCR2 began within 2 hrs. This gene expression lasted for 4 hrs and decreased afterwards. Under the blue light (470 nm) condition, the expression of this gene was induced in same way as HL treatment, even under less than 100 μmol photon m–2 s–1. But red light (650 nm) and UV-A irradiation did not affect the expression of SVCR2.

• The Plant Pathology Journal
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• v.24 no.1
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• pp.93-96
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• 2008

In August 2006, a severe disease incidence showing mosaic and/or necrotic symptoms on two bell pepper varieties including red-colored 'Special' and yellow-colored 'Fiesta' was observed in a greenhouse located in Gwangyang, Jeonnam province, Korea. To identify causal viruses, total RNAs were extracted from 11 fruit samples with and without symptoms. Specific oligonucleotide primers for Cucumber mosaic virus (CMV), Pepper mottle virus (PepMoV), Tomato spotted wilt virus (TSWV) and Pepper mild mottle virus (PMMoV) were designed based on the sequences available on GenBank. Database comparisons of the deduced amino acid sequences of each sequence produced 100% and 98% matches with nucleocapsid protein gene of TSWV (Acc. No. ABE11605) and coat protein gene of CMV (Acc. No. DQ018289), respectively, suggesting that the symptoms on bell pepper fruits might be caused by the infection of CMV and TSWV. To our knowledge this is the first report of necrotic as well as mosaic virus disease on bell pepper fruits by the infection of CMV and TSWV in Jeonnam province, Korea.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.04a
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• pp.77-78
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• 2003

A novel -1, 4-endoglucanase (EGase, EC 3.2.1.4) cDNA belonging to glycoside hydrolase family (GHF) 45 was cloned from the mulberry longicorn beetle, Apriona germari. The cDNA encoding EGase of A. germari (Ag-EGase) is 711 base pairs long with an open reading frame of 237 amino acid residues. The deduced protein sequence of Ag-EGase showed 54% and 48% identity to phytophagous beetle Phaedon cochleariae and termite Reticulitermes speratus hindgut symbiont, respectively. (omitted)

• BMB Reports
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• v.42 no.3
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• pp.172-177
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• 2009

Phosphoglucose isomerase (PGI) is involved in synthesizing extracellular polysaccharide (EPS). The gene encoding PGI in Sphingomonas chungbukensis DJ77 was cloned and expressed in E. coli, and the protein was characterized. The pgi gene from DJ77 is 1,503 nucleotides long with 62% GC content and the deduced amino acid sequence shows strong homology with PGIs from other sources. The molecular masses of PGI subunit and native form were estimated to be 50 kDa and 97 kDa, respectively. Four potentially important residues (H361, R245, E330 and K472) were identified by homology modeling. The mutations, H361A, R245A, E330A, R245K and E330D resulted in decrease in Vmax by hundreds fold, however no significant change in Km was observed. These data suggest that the three residues (H361, R245Aand E330) are likely located in the active site and the size as well as the spatial position of side chains of R245 and E330 are crucial for catalysis.

• The Journal of the Korean Society for Microbiology
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• v.35 no.2
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• pp.109-115
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• 2000

FtsH is a membrane-bound, ATP-dependent metalloprotease that is involved in a variety of cellular functions including the regulation of responses to heat and stress shock. Previously, we had cloned and sequenced pneumococcal ftsH gene whose deduced amino acid sequence was very similar to those of several gram-positive bacteria and Escherichia coli, except for the N-terminal domain that was responsible for membrane anchoring. In order to better understand the role of Streptococcus pneumoniae FtsH, we expressed pneumococcal ftsH gene in Escherichia coli. When it was expressed from a strong promoter, $P_{tac}$, a considerable amount of the recombinant FtsH was produced, although the prolonged induction resulted in not only accumulation of breakdown products but also ceasing of the further growth of E. coli host. This indicated that the expression of the exogenous ftsH gene was tightly regulated since the excessive FtsH appeared detrimental to bacterial cells. In Western blotting, the pneumococcal FtsH protein, whether native or recombinant, was reactive to anti-E. coli FtsH serum. The observation that FtsH proteins were well conserved throughout the bacterial kingdom and its expression level was fine-tuned suggests an important role for this protein in the stress adaptation which may be related to infecting process by pneumococci.

• The Plant Pathology Journal
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• v.20 no.2
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• pp.131-134
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• 2004

A strain of Cucumber mosaic virus (CMV) was isolated from a weed, water chickweed (Stellaria aquatica), growing in the pepper field in Chunchon, Korea. This isolate, CMV-Sa, was differentiated from other CMVs based on biological properties and nucleotide sequence analysis of the coat protein (CP) gene. CMV-Sa showed different reactions to all the tested plants, except Capsicum annuum and Cucumis sativus, when compar-ed with those of CMV-Mf (subgroup I) and CMV-PaFM (subgroup II). Remarkably, in Nicotiana tabacum cvs. Samsun, Xanthi-nc and Ky-57, CMV-Sa induced local necrotic ring spots on the inoculated leaves and venal wave pattern and mosaic on the upper leaves. RNA analysis, serology, and RT-PCR of CP gene showed that CMV-Sa belonged to subgroup I of CMV. However, restriction enzyme analysis of the cDNA using AluI, HhaI, HincII, HindIII, HinfI and MspI showed that CMV-Sa was distinct from that of CMV-Mf. Based on comparison of the nucleotide of CP gene and deduced amino acid sequences between other CMV strains, CMV-Sa was closely related to CMV-Mf with 93.7% and 97.2 % identity, respectively.