Proline utilization in Saccharomyces cerevisiae: sequence, regulation, and mitochondrial localization of the PUT1 gene product.

Abstract

The PUT) gene of Saccharomyces cerevisiae, believed to encode proline oxidase, has been completely sequenced and contains an open reading frame capable of encoding a polypeptide of 476 amino acids in length. The amino terminus of the protein deduced from the DNA sequence has a characteristic mitochondrial import signal; two PUT)-lacZ gene fusions were constructed that produced mitochondrially localized ,(-galactosidase in vivo. The transcription initiation and termination sites of the PUT) mRNA were determined. By using a PUT)-lacZ gene fusion that makes a cytoplasmic jI-galactosidase, the regulation of the PUT) gene was studied. PUT) is inducible by proline, responds only slightly to carbon catabolite repression, and is not regulated by the cytochrome activator proteins HAPI and HAP2.

Elucidation of the Role of Nitrogenous Wort Components in Yeast Fermentation

“…4 and 5), with methionine (group B) noted to be removed from the wort rapidly by the yeast. As expected, proline exhibited almost no uptake, due to the requirement for oxygen and a functioning electron transport chain for proline metabolism 21 .…”

The sluggish-A gene of Drosophila melanogaster is expressed in the nervous system and encodes proline oxidase, a mitochondrial enzyme involved in glutamate biosynthesis.

“…Analysis of the amino acid sequence of the predicted slgA protein reveals that a region of 165 amino acids toward the C terminus exhibits 30% sequence identity and 69% similarity to part of the proline oxidase encoded by the PUT) gene of S. cerevisiae (27) (Fig. 6).…”

Role of the non‐respiratory pathways in the utilization of molecular oxygen by Saccharomyces cerevisiae

“…PUT1 is induced by L-proline and is strongly downregulated under anaerobic conditions. 191,208 However, during anaerobic enological fermentation (strong glucose repression), it has been shown that L-proline is rapidly metabolized after moderate oxygen addition at the end of the growth phase. 172 This practice is of great biotechnological importance, since natural musts often contain limiting amounts of potentially assimilated nitrogen, and since L-proline is one of the more abundant amino acids in these media.…”