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The characterization of the catalytic region of Ira2p, a GTPase-activating protein, in Saccharomyces cerevisiae reveals that the active site is highly conserved. Monovalent and divalent salts suppress the activity of Ira2p-383 fragment. The enzyme is similar to mammalian p120-GAP neurofibromin, and incorporates a binding site for tubulin, which inhibits both Ira2p and neurofibromin. This binding site extends to the N-terminal flanking region of the enzyme.

The primary and secondary structure of the cyanide adduct of a triple mutant iso-1-cytochrome c of Saccharomyces cerevisiae obtained from an analyses of the (super 1)H NMR spectrum is given. The quality of the mutant protein as determined by the RMSD values is similar to the ferrocytochrome c of the horse heart. The secondary structure and folding of the mutant is similar to that of the wild-type protein. A distal ligand-binding cavity is formed by if alanine is present instead of the axial ligand. Due to four prolines which do not contain amide NH there is no connectivity in the amino acid sequence.

Beta1,3-coupled disaccharides comprising the type I and type IV core disaccharide of carbohydrate-containing antigens are obtained by the glycosidase-mediated coupling of glycal acceptors with galactose. The beta1, 3-coupled disaccharide serves as an intermediary in chemical and enzymatic manipulation. An enzyme, beta1,6-N-acetylglucosaminyltransferase, facilitates the modification of the type IV disaccharide to a mucin-type trisaccharide, by a transfer of N-acetylglucosamine, to the 6-hydroxy position of N-acetylgalactosamine or galactose-reducing terminus.

The first description of entire, uniform isotopic labeling of a eukaryotic cytochrome c, iso-1-cytochrome c from the Saccharomyces cerevisiae yeast, is presented. Heteronuclear NMR methods could be used to assign resonances, measure amide hydrogen exchange rates and calculate relaxation parameters, due to sufficient quantities of super15N-labeled protein.

A five-step synthetic strategy helps prepare the antifungal agent (+)-preussin from t-Boc-(S)-phenylalanine. The stereoselective synthesis of (+)-preussin involves a Hg(II)-mediated 5-endo-dig ring closure of a ynone. Examination of (+)-preussin with a strain of Saccharomyces cerevisiae, which is deficient in recombinational DNA repair, reveals pressuin to be a DNA damaging agent in yeast.