Thesis Research

* Summer Research Assistant and Senior Project in Biology
Cynthia Mondesir '95

"Identification of a novel yeast amino acid permease gene"


The amino acid leucine has been shown to be transported into a yeast cell by three permeases: the general amino acid permease, a high affinity permease (S1) and a low affinity permease (S2). We isolated the gene BAP2 as a multicopy suppressor of the YPD- phenotype of aat1leu2 yeast. BAP2 has been identified previously as encoding an amino acid permease which transports branched chain amino acids. In order to align the genetic and biochemical studies of leucine uptake we completed a detailed kinetic analysis of yeast strains in which the BAP2 gene was disrupted and compared this to the kinetics of uptake of the parental strain. We demonstrate that BAP2 encodes the high affinity leucine permease previously called S1.

Cynthia presented her research at Union College, XIX Annual Biological Sciences Research Symposium, SUNY - Binghampton, NY in November 94 and at the 9th National Conference on Undergraduate Research, Union College, Schenectedy, NY April 95.

The project Cynthia initiated has recently been published:

Schreve, J. and Garrett, J. 1997. The branched chain amino acid permease gene of S. cerevisiae, BAP2, encodes the high affinity leucine permease (S1). Yeast 13, 435-439.