Involvement of transglutaminase in the formation of covalent cross-links in the cell wall of Candida albicans

Abstract

Activity of the enzyme glutaminyl-peptide--glutamylyl-transferase (EC 2.3.2.13; transglutaminase), which forms the interpeptidic cross-link N epsilon-(gamma-glutamic)-lysine, was demonstrated in cell-free extracts obtained from both the yeast like and mycelial forms of Candida albicans. Higher levels of enzymatic activity were observed in the cell wall fraction, whereas the cytosol contained only trace amounts of activity. Cystamine, a highly specific inhibitor of the enzyme, was used to analyze a possible role of transglutaminase in the organization of the cell wall structure of the fungus. Cystamine delayed protoplast regeneration and inhibited the yeast-to-mycelium transition and the incorporation of proteins into the cell wall. The incorporation of covalently bound high-molecular-weight proteins into the wall was sensitive to cystamine. Proteic epitopes recognized by two monoclonal antibodies, one of which is specific for the mycelial walls of the fungus, were also sensitive to cystamine. These data suggest that transglutaminase may be involved in the formation of covalent bonds between different cell wall proteins during the final assembly of the mature cell wall.

Transglutaminase-like activity participates in cell wall biogenesis in Saccharomyces cerevisiae

“…Taken together, our experimental results justify the assumption about the participation of TGase-like activity in the cell wall biogenesis of yeast S. cerevisiae (Ruiz-Herrera et al 1995;Iranzo et al 2002). The arguments in favor of this hypothesis are as follows: (i) [ 3 H]putrescine incorporation into the isolated cell walls that was increased by adding the artificial TGase substrate N,N'-dimethylcasein; (ii) […”

“…14 C]putrescine into the isolated cell walls of yeast and mycelial form Candida albicans was previously demonstrated by Ruiz-Herrera et al (1995). They used cystamine, a highly specific inhibitor of TGase (Lorand & Konrad 1984), to ascertain a possible role of TGase in the organization of cell wall structure in the fungus.…”

“…Cystamine delayed protoplast regeneration and inhibited the yeast-to-mycelium transition and the incorporation of proteins into the cell wall. The incorporation of covalently bound high-molecular-weight proteins into the cell wall was also sensitive to cystamine (Ruiz-Herrera et al 1995).…”

Inhibition of α-ketoglutarate-and pyruvate dehydrogenase complexes in E. coli by a glutathione S-transferase containing a pathological length poly-Q domain: A possible role of energy deficit in neurological diseases associated with poly-Q expansions?

“…Streptoverticillium sp. (16) andCandida albicans (17) have recently been shown to possess transglutaminase activity. In these organisms, transglutaminase is possibly a catalyst for the strengthening of cell walls.…”

Optimization of transconjugation and characterization of attB integration site for Streptomyces cinnamoneus producing transglutaminase

“…They are also widely present in most animal tissues and body fluids (Folk 1983;Lorand & Conrad 1984). TGases have been discovered in microorganisms including Candida albicans (Ruiz-Herrera et al 1995), Bacillus subtilis (Kobayashi et al 1996), Escherichia coli (Schmidt et al 1998), Physarum polycephalum (Klein et al 1992), and actinomycetes (Kanaji et al 1993;Gerber et al 1994;Duran et al 1998).…”