Flocculation of Saccharomyces cerevisiae is induced by transformation with the GAP1 gene from Kluyveromyces marxianus

Abstract

A non-¯occulent strain of Saccharomyces cerevisiae was transformed with the GAP1 gene which encodes p37, a GAPDH-like protein present in the cell wall of Kluyveromyces marxianus¯occulent cells. The transformed cells were characterized with respect to¯occulation behaviour, morphology, growth, cell wall integrity and GAPDH activity. A¯occulent phenotype was acquired by the transformed cells, showing a behaviour in respect tō occulation/de¯occulation very similar to that of K. marxianus. The presence of p37 in the cell wall was assessed by immunoprecipitation of biotinylated cell wall proteins and an accumulation of p37 was evident in the cell wall of transformed cells. This result was con®rmed by studies using a chimeric protein resulting from fusing the p37 with a yeast-enhanced green¯uorescent protein, yEGFP. The recombinant protein was localized mainly in the cell wall of the transformed strain, although the presence of p37 in the cytosol was indicated by an increase in GAPDH activity. Calco¯uor white sensitivity tests indicated that the cell wall structure is affected by the accumulation of p37. These results provided further evidence of p37 function regarding¯occulation and that although lacking a N-terminal signal peptide p37 is targeted to the cell wall.

Enzymes on microbial pathogens andTrichomonas vaginalis: molecular mimicry and functional diversity

“…This binding of fibronectin by GAPDH is distinct from that which occurs through Candida surface integrin‐like receptors (DeMuri and Hostetter, 1996; Hostetter, 1996, 1999). (4) Moreover, a multigene family of GAPDH exists for Kluyveromyces marxianus , and only one member of this family, p37 or GAP1, resides on the cell wall and mediates flocculation (Fernandes et al ., 1992, 1993, 1995; Moreira, et al ., 2000). Interestingly, regulation of expression of GAP1 may result from carbon sources different from those important for the other GAPDH genes.…”

Comparative analyses of three legume species reveals conserved and unique root extracellular proteins

“…Glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) is generally considered as a cytoplasmic marker, and has been associated with extracellular functions . GAPDH has been demonstrated to be a secreted protein in many organisms including bacteria and yeast . The expression of GAPDH is induced under environmental stress, such as heat shock and anerobic stress .…”

Applications of yeast flocculation in biotechnological processes

“…Recently, the overexpression of the Kluyveromyces marxianus GAP1 gene, encoding for the p37 protein, in Saccharomyces cerevisiae, resulted in flocculation of the transformed yeast strain [99]. The transformed strain exhibited a flocculation/deflocculation phenotype very similar to that of K. marxianus.…”

“…More recently, the transfer of the flocculation property to a non-flocculent S. cerevisiae by cloning the heterologous gene GAP1 from K. marxianus has been reported [99].…”