Clostridium perfringens, an α-toxin producing gram-positive bacterium, is an enteric pathogen for poultry. Because subclinical C. perfringens infections often result in damage of the intestinal mucosa, decreased nutrient digestion, and poor performance, efforts should be taken to find an effective strategy that controls overgrowth of C.
View Article and Find Full Text PDFMol Biochem Parasitol
April 1994
The enzyme dihydrolipoamide dehydrogenase has been discovered and characterised in four salivarian trypanosomes of the subgenus trypanozoon: Trypanosoma brucei brucei, T. b. gambiense, T.
View Article and Find Full Text PDFA gene encoding dihydrolipoamide dehydrogenase was isolated from Trypanosoma brucei genomic DNA by using a combination of polymerase chain reaction and screening of a lambda EMBL3 library. The DNA sequence reveals that it encodes a protein of 478 amino acids (M(r) 49935) highly similar to previously sequenced dihydrolipoamide dehydrogenases. The gene was ligated into pMEX8 and expressed in an Escherichia coli mutant that lacks dihydrolipoamide dehydrogenase.
View Article and Find Full Text PDFEur J Biochem
September 1991
Tetrameric Escherichia coli phosphofructokinase dissociates reversibly on incubation under hydrostatic pressures of 80 MPa and above, yielding inactive dimers and monomers. The transition is dependent upon enzyme concentration and presence of ligands. The substrate, D-fructose 6-phosphate, which bridges the intersubunit interface at the active site, produces a massive stabilization to pressure, whereas ATP, which binds to only one subunit, induces only a mild stabilization.
View Article and Find Full Text PDFSingle nucleotide changes to the sequence between two alternative 5' splice sites, separated by 25 nucleotides in a beta-globin gene derivative, caused substantial shifts in pre-mRNA splicing preferences, both in vivo and in vitro. An activating sequence for splicing was located. Models for the recognition by U1 small nuclear ribonucleoproteins (snRNPs) of competing 5' splice sites were tested by altering the distance separating the two sites.
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