Transglutaminase activity is involved in Saccharomyces cerevisiae wall construction.
Transglutaminase activity, which forms the interpeptidic cross-link N(epsilon)-(gamma-glutamyl)-lysine, was demonstrated in cell-free extracts of Saccharomyces cerevisiae by incorporation of [(14)C]lysine into an exogenous acceptor, N,N'-dimethylcasein. Higher levels of the activity were present in the cell wall, which also contained endogenous acceptors. The enzyme activity in the wall was inhibited by cystamine, a known inhibitor of transglutaminase, and by EDTA, indicating a cation-dependent activity. After the endogenous wall acceptors were labelled radioactively by transglutaminase, extraction with SDS solubilized about 50% of the total radioactivity, while Zymolyase and chitinase each released a further 3%. The proteins solubilized by SDS had molecular masses less than 50 kDa, whereas the material released by Zymolyase or chitinase had molecular masses greater than 180 kDa, suggesting a precursor-product relationship. Cystamine inhibited the growth of several strains of S. cerevisiae. Treated cells showed increased sensitivity to Zymolyase and appeared as protoplasts, indicating gross alterations in the cell wall. These data suggest that transglutaminase may be involved in the formation of covalent cross-links between wall proteins during wall construction.
Iranzo
Marı A
MA
Sección de Microbiologı́a, Facultad de Farmacia, Universidad de Valencia, Avda V. Andrés Estelles s/n, 46100 Burjassot (Valencia), Spain1.
Aguado
Carmen
C
Sección de Microbiologı́a, Facultad de Farmacia, Universidad de Valencia, Avda V. Andrés Estelles s/n, 46100 Burjassot (Valencia), Spain1.
Pallotti
Claudia
C
Sección de Microbiologı́a, Facultad de Farmacia, Universidad de Valencia, Avda V. Andrés Estelles s/n, 46100 Burjassot (Valencia), Spain1.
Cañizares
Jose V
JV
Sección de Microbiologı́a, Facultad de Farmacia, Universidad de Valencia, Avda V. Andrés Estelles s/n, 46100 Burjassot (Valencia), Spain1.
Mormeneo
Salvador
S
Sección de Microbiologı́a, Facultad de Farmacia, Universidad de Valencia, Avda V. Andrés Estelles s/n, 46100 Burjassot (Valencia), Spain1.
D002457:Cell Extracts; D002473:Cell Wall / Q000737:chemistry* / Q000187:drug effects / Q000378:metabolism*; D003538:Cystamine / Q000494:pharmacology; D004693:Glucan Endo-1,3-beta-D-Glucosidase / Q000378:metabolism; D008239:Lysine / Q000378:metabolism; D011523:Protoplasts / Q000187:drug effects / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development; D011503:Transglutaminases / Q000037:antagonists & inhibitors / Q000378:metabolism*
D002457:Cell Extracts; D011503:Transglutaminases; D004693:Glucan Endo-1,3-beta-D-Glucosidase; D008239:Lysine; D003538:Cystamine