A vacuolar membrane protein Vsb1p contributes to the vacuolar compartmentalization of basic amino acids in Schizosaccharomyces pombe

Abstract

Accumulation levels of Arg, Lys, and His in vacuoles of Schizosaccharomyces pombe cells were drastically decreased by the disruption of spac24h6.11c+ (vsb1+) gene identified by a homology search with the VSB1 gene of Saccharomyces cerevisiae. The Vsb1p fused with green fluorescent protein particularly localized at vacuolar membranes in S. pombe cells. Overexpression of vsb1+ markedly increased vacuolar levels of basic amino acids; however, overexpression of the vsb1D174A mutant did not affect the levels of these amino acids. These results suggest that the vsb1+ contributes to the accumulation of basic amino acids into the vacuoles of S. pombe and the aspartate residue in the putative 1st transmembrane domain conserved among fungal homologs is crucial for the function of Vsb1p.

Designing Intracellular Compartments for Efficient Engineered Microbial Cell Factories

“…Vacuolar storage contributes to AdoMet accumulation and enables yeast to tolerate high levels of AdoMet. Ohnishi et al also proved that the overexpression of Vsb1p in the vacuole of Schizosaccharomyces pombe contributed to the accumulation of basic amino acids in the vacuole …”

“…Ohnishi et al also proved that the overexpression of Vsb1p in the vacuole of Schizosaccharomyces pombe contributed to the accumulation of basic amino acids in the vacuole. 77 The chloroplast is considered to be a feasible compartment for the synthesis of highly valuable bioactive compounds such as diterpenoids. The synthesis of complex plant natural products requires the introduction of membrane-located enzymes, including P450.…”