An alkaline cellulase from Bacillus sp. HSH-810 was purified 8.7-fold with a 30% yield and a specific activity of 71 U mg(-1) protein. It was optimally active at pH 10 and 50 degrees C and was stable from pH 6 to 10 with more than 60% activity remaining after heating at 60 degrees C for 60 min. The molecular mass of cellulase was 80 kDa. It was inhibited by 50% by Fe3+ (1 mM) and Mn2+ (0.1 mM) but was relatively insensitive to Hg2+ and Pb2+ at 1 mM.

Mass production of glucosamine (GlcN) using microbial cells is a worthy approach to increase added values and keep safety problems in GlcN production process. Prior to set up a microbial cellular platform, this study was to assess acetate metabolism in Citrobacter sp. BL-4 (BL-4) which has produced a polyglucosamine PGB-2. The LC-MS analysis was conducted after protein separation on the 1D-PAGE to accomplish the purpose of this study. 280 proteins were totally identified and 188 proteins were separated as acetate-related proteins in BL-4. Acetate was converted to acetyl-CoA by acetyl-CoA synthetase up-regulated in the acetate medium. The glyoxylate bypass in the acetate medium was up-regulated with over-expression of isocitrate lyases and 2D-PAGE confirmed this differential expression. Using 1H-NMR analysis, the product of isocitrate lyases, succinate, increased about 15 times in the acetate medium. During acetate metabolism proteins involved in the lipid metabolism and hexosamine biosynthesis were over-expressed in the acetate medium, while proteins involved in TCA cycle, pentose phosphate cycle and purine metabolism were down-regulated. Taken together, the results from the proteomic analysis can be applied to improve GlcN production and to develop metabolic engineering in BL-4.

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Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most prevalent dermatology pathogens in hospitals and increasingly recognized in communities. We determined PFGE pattern of SmaI-restricted genomic DNA, coagulase type, and antimicrobial susceptibility of MRSA isolated in 2008 from dermatology inpatients and healthy hospital employees in A Hospital and from primary school children in Iksan city, Korea. Overall, the isolation rate of MRSA was 3.8% from the 788 normal persons: 4.9% from hospital employees and 1.1% from primary school children. MRSA was isolated in six of 13 (46.2%) family members of four school children with MRSA. The most prevalent coagulase serotype was II from patients and V from healthy individuals. Ten of twenty and six of twenty MRSA isolates from patients and from healthy personnel, respectively, had identical PFGE patterns, suggesting that these are originated from identical clones. Against MRSA from patients, only vancomycin was the most active (MIC range ≤2 μg/ml), whereas the resistance rates were 35% to rifampin and 65% to mupirocin. The resistance rates of patient isolates were ≥90% to amikacin, clindamycin, ciprofloxacin, erythromycin, fusidic acid, gentamicin and tetracycline. In conclusion, the MRSA carriage rates of healthy hospital workers were relatively high, 2.3~7.7%, depending on groups. Family members of a few primary school children with MRSA showed a high carriage rate, suggesting that intrafamily transmission occurred. MRSAs isolated from dermatology inpatients were relatively more resistant to various antimicrobial agents, including mupirocin, but all isolates were susceptibility to vancomycin.