• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 가을 학술논문 발표대회
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• pp.159-160
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• 2020

This study examined the potentials for developing a biological coating material with high chloride resistance. The bacteria strains isolated were Halomonas alkaliphile, Halomonas venusta, and Sulfidobacter mediterraneus. Test results revealed that the developed approach is very promising in reducing the chloride ion diffusion coefficient of concrete.

• Journal of Microbiology and Biotechnology
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• 제18권12호
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• pp.1908-1914
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• 2008

An alkaliphilic bacterium, Bacillus clausii SKAL-16, was isolated from soil that had been contaminated with vegetable oil. The optimal pH and general pH range for bacterial growth was 8, and 7 to 10, respectively. The bacterium could grow on tributyrin and glycerol, but could not grow on acetate and butyrate. The SKAL-16 strain excreted butyric acid during growth on tributyrin, and selectively ingested glycerol during growth on a mixture of butyric acid and glycerol. The SKAL-16 generated intracellular lipase, but did not produce esterase and extracellular lipase. The DNA fragment amplified with the chromosomal DNA of SKAL-16 and primers designed on the basis of the esterase-coding gene of Bacillus clausii KSM-KI6 was not identical with the esterase-coding gene contained in the GenBank database. Pyruvate dehydrogenase, isocitrate dehydrogenase, and malate dehydrogenase activities were detected in the cell-free extract (crude enzyme).

• Journal of Microbiology and Biotechnology
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• 제20권4호
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• pp.670-677
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• 2010

An alkaline pectate lyase, Bsp165PelA, was purified to homogeneity from the culture broth of alkaliphilic Bacillus sp. N16-5. The enzyme showed a specific activity as high as 1,000 U/mg and had optimum activity at pH 11.5 and $50^{\circ}C$. It was composed of a single polypeptide chain with a molecular mass of 42 kDa deduced from SDS-PAGE, and its isoelectric point was around pH 6.0. It could efficiently depolymerize polygalacturonate and pectin. Characterization of product formation revealed unsaturated digalacturonate and trigalacturonate as the main products. The pectate lyase gene (pelA) contained an open reading frame (ORF) of 1,089 bp, encoding a 36-amino acids signal peptide and a mature protein of 326 amino acids with a calculated molecular mass of 35.943 Da. The deduced amino acid sequence from the pelA ORF exhibited significant homology to those of known pectate lyases in polysaccharide lyase family 1. Some conserved active-site amino acids were found in the deduced amino acid sequence of Bsp165PelA. $Ca^{2+}$ was not required for activity on pectic substrates.

• Journal of Microbiology and Biotechnology
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• 제25권12호
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• pp.1971-1976
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• 2015

Oceanobacillus kimchii is a member of the genus Oceanobacillus within the family Bacillaceae. Species of the Oceanobacillus possess moderate haloalkaliphilic features and originate from various alkali or salty environments. The haloalkaliphilic characteristics of Oceanobacillus advocate they may have possible uses in biotechnological and industrial applications, such as alkaline enzyme production and biodegradation. This study presents the draft genome sequence of O. kimchii X50^T and its annotation. Furthermore, comparative genomic analysis of O. kimchii X50^T was performed with two previously reported Oceanobacillus genome sequences. The 3,822,411 base-pair genome contains 3,792 protein-coding genes and 80 RNA genes with an average G+C content of 35.18 mol%. The strain carried 67 and 13 predicted genes annotated with transport system and osmoregulation, respectively, which support the tolerance phenotype of the strain in high-alkali and high-salt environments.