Kex2-dependent processing of yeast K1 killer preprotoxin includes cleavage at ProArg-44
Department of Molecular Genetics and Microbiology; Department of Microbiology and Physiological Systems
Microbiology | Physiology
The K1 killer toxin of Saccharomyces cerevisiae consists of 103- and 83-residue alpha and beta components whose derivation, from a 316-residue precursor preprotoxin, requires processing at the alpha N-terminus (after ProArg-44), the alpha C-terminus (after ArgArg-149) and at the beta N-terminus (after LysArg-233). These processing events occur after translocation to the Golgi and have been investigated using beta-lactamase fusions. Signal peptidase cleavage of the precursor, predicted to occur after Ala-26, was confirmed by N-terminal sequence analysis of Ala-34 and Ile-52 fusions. Cleavage at all of the other predicted processing sites, including ProArg-44, is dependent on activity of the Kex2 protease. A fourth Kex2-dependent cleavage occurs at LysArg-188. Implications for the specificity of Kex2 cleavage and preprotoxin processing are discussed.
DOI of Published Version
Mol Microbiol. 1992 Feb;6(4):511-20.
Zhu, Yun Song; Zhang, Xia Ying; Cartwright, Charles P.; and Tipper, Donald J., "Kex2-dependent processing of yeast K1 killer preprotoxin includes cleavage at ProArg-44" (1992). Microbiology and Physiological Systems Publications and Presentations. 66.