ABSTRACT
For syntheses of recombinant yellowtail and flounder growth hormones (r-yGH and r-fGH) in E. coli, expression plasmids were constructed. The expression level of r-yGH and r-fGH in the host cells were very high, reaching 15 and 8% of the total protein, respectively. These product proteins were accumulated in inclusion bodies in the cells. The recombinant hormones were isolated from the pellets ina glutathione reduction/oxidation buffer. The refolded hormones were further purified by DEAE-Toyopearl 650M chromatography to homogeneity. The purified r-yGH and r-fGH were composed of 188 and 174 amino acid residues, respectively, having amino-terminal sequences starting with methionine. The recombinant hormones had potent growth-promoting activities on juvenile rainbow trout Salmo gairdneri in a dose-dependent manner.
Subject(s)
Growth Hormone/biosynthesis , Growth Hormone/genetics , Animals , Base Sequence , Biotechnology , DNA, Recombinant/genetics , Escherichia coli/genetics , Fishes/genetics , Flounder/genetics , Genetic Vectors , Growth Hormone/pharmacology , Molecular Sequence Data , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , Recombinant Proteins/pharmacology , Trout/growth & developmentABSTRACT
Metabolic and antiproliferative effects of methylglyoxal bis(butylamidinohydrazone) (MGBB) and methylglyoxal bis(cyclopentylamidinohydrazone) (MGBCP), inhibitors for polyamine biosynthetic pathway, on Escherichia coli, Shigella sonnei, Aeromonas sobria, Aeromonas hydrophila and Vibrio cholerae were investigated. MGBB at the concentration of 100 mumol/l depleted intracellular putrescine and spermidine concentrations of E. coli to 25 and 20% of the controls, respectively, while MGBCP depressed their concentrations to 38 and 24%, respectively. In these polyamine-depleted E. coli cells the syntheses of RNA, DNA and protein decreased to 13, 54 and 29% of the control, respectively, with MGBB and to 23, 71 and 55%, respectively, with MGBCP. The minimum inhibitory concentrations (MIC) of MGBB for the growth of A. sobria, E. coli, A. hydrophila, V. cholerae and Sh. sonnei were estimated to be 50, 160, 240, 285 and 320 mumol/l, respectively, whereas those of MGBCP were slightly higher for respective bacteria.
Subject(s)
Bacteria/drug effects , Biogenic Polyamines/biosynthesis , Mitoguazone/analogs & derivatives , Bacteria/growth & development , Bacterial Proteins/biosynthesis , Escherichia coli/metabolism , Mitoguazone/pharmacologyABSTRACT
15-Deoxyspergualin (DSG), an immunosuppressive agent used in organ transplantation, exerts metabolic and antiproliferative effects on methicillin- and gentamicin-resistant Staphylococcus aureus and other bacteria (e.g. Sarcina lutea, Bacillus subtilis, Shigella sonnei, Salmonella typhi and Citrobacter freundii). DSG, at the concentration of 20 mg/l, depleted intracellular putrescine and spermidine in S. aureus to 43 and 40% of the controls, respectively. In these polyamine-depleted S. aureus cells, the synthesis of protein, DNA and RNA was decreased to 20, 85, 78% of the controls. The minimal inhibitory concentrations (MIC) of DSG for growth of S. aureus, S. lutea, B. subtilis, S. sonnei, S. typhi and C. freundii were 17, 13, 7, 15, 4, and 29 mg/l, respectively.
