RESUMO
Photorhabdus luminescens, a bacterial symbiont of entomopathogenic biocontrol nematodes, was grown in batch and glucose fed-batch culture. The cell density, bioluminescence, production of antibiotic substances, number of cells with inclusion bodies, glucose concentration and oxygen uptake rate were recorded. The addition of 12.4 g 1(-1) glucose prolonged the growth, and the yield almost doubled, from 6.85 g 1(-1) to 12.45 g 1(-1) dry mass. The production of antibiotic substances increased by 140%. Bioluminescence was higher in the batch culture. A shift of P. luminescens to phase II variants was not detected.
Assuntos
Reatores Biológicos , Glucose/metabolismo , Photorhabdus/crescimento & desenvolvimento , Antibacterianos/biossíntese , Contagem de Colônia Microbiana , Meios de Cultura , Corpos de Inclusão/metabolismo , Medições Luminescentes , Consumo de Oxigênio , Photorhabdus/metabolismoRESUMO
The anaphylatoxic peptide C5a is an important inflammatory mediator of the complement system. We have generated human C5a-receptor (hC5aR) mutants with truncation of its cytosolic carboxyl-terminus (C-terminus). Both mutants were analysed for C5a-binding in transiently expressing COS cells, and one mutant additionally for GTP-binding regulatory protein (G-protein) coupling in cRNA-injected Xenopus oocytes. Our data suggest that (a) amino acids (aa) 314 to 326 as part of the C-terminus are necessary for proper receptor folding or expression and (b) the receptor C-terminus distal from position 327 is not critical for receptor expression, folding, binding and G-protein coupling.
