Mutant strains of bacteria

General objectives: Creating of attenuated mutant Vibrio parahaemolyticus strains causing immune response for fish to develop production of vaccines against nephrotic and hepatic necrosis disease for some marine fish.

27p tunelove 10-06-2021 10 3   Download

The Saccharomyces cerevisiae type 2A protein phosphatase (PP2A) Pph22p differs from the catalytic subunits of PP2A (PP2Ac) present in mammals, plants and Schizosaccharomyces pombe by a unique N-terminal extension of approximately 70 amino acids. We have overexpressed S. cerevisiae Pph22p and its N-terminal deletion mutant DN-Pph22p in the GS115 strain of Pichia pastoris and purified these enzymes to apparent homogeneity.

11p research12 01-06-2013 45 5   Download

Osmoregulated periplasmic glucans (OPGs) ofRhodobacter sphaeroidesare anionic cyclic molecules that accumulate in large amounts in the periplasmic space in response to low osmolarity of the medium. Their anionic character is pro-vided by the substitution of the glucosidic backbone by succinyl residues. A wild-type strain was subject to trans-poson mutagenesis, and putative mutant clones were screened for changes in OPGs by thin layer chromatogra-phy.

12p research12 29-04-2013 43 6   Download

Previously, a phase-variable epitope was detected in the virulent wild-type strain RC1 of Legionella pneumophila serogroup 1 subgroup OLDA using a lipopolysaccharide-speci®c monoclonal antibody, mAb 2625 [LuÈneberg, E., ZaÈhringer,U.,Knirel,Y.A., Steinmann,D.,Hartmann,M., Steinmetz, I., Rohde, M., Kohl, J. & Frosch, M. (1998) J. Exp. Med.188, 49±60]. In the present study, an isogenic mutant strain, termed 5215, was constructed by deletion of genes involved in the biosynthesis of the mAb 2625 epitope....

13p research12 23-04-2013 29 3   Download

PhotobacteriumphosphoreumIFO13896 emits light strongly when cultured in medium containing 3% NaCl, but only weakly in medium containing 1% NaCl.It is known that dim or dark mutants appear frequently and spontaneously from this parent strain.To confirm that riboflavin biosyn-thesis is stimulatedwhen theluxoperon is active, the amount of light emitted and flavins synthesized under strongly or weakly light emitting conditions was determined.

10p tumor12 22-04-2013 27 5   Download