Phosphatidylinositol-Specific Phospholipase C of Bacillus cereus: Cloning, Sequencing, and Relationship to Other Phospholipases
Dateien
Datum
1989-11
Zeitschriftentitel
ISSN der Zeitschrift
Bandtitel
Verlag
Journal of Bacteriology
Zusammenfassung
The phosphatidylinositol (Pl)-specific phospholipase C (PLC) of Bacillus cereuswas cloned into Escherichia
coli by using monoclonal antibody probes raised against the purified protein. The enzyme is specific for
hydrolysis of the membrane lipid PI and Pl-glycan-containing membrane anchors, which are important
structural componentsof one class of membrane proteins. The protein expressedin E. colicomigrated with B.
cereus PI-PLC in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, as detected by immunoblotting,
and conferred PI-PLC activity on the host. This enzyme activity was inhibited by PI-PLC-specific monoclonal
antibodies. The nucleotide sequence of the PI-PLC gene suggests that this secreted bacterial protein is
synthesized as a larger precursor with a 31-amino-acid N-terminal extension to the mature enzyme of 298
amino acids. From analysis of coding and flanking sequences of the gene, weconclude that the PI-PLC gene
does not reside next to the gene cluster of the other two secreted phospholipases C on the bacterial chromosome.
The deduced amino acid sequence of the B. cereus PI-PLC contains a stretch of significant similarity to the
glycosylphosphatidylinositol-specific PLCof Trypanosoma brucei. The conserved peptide is proposed to playa
role in the function of these enzymes.
Beschreibung
14 pages