Preliminary work on a crude in vitro system for glutamic-γ-semialdehyde
synthesis in Escherichia coli has been described. The
cell extract synthesis of GSA is inhibited by proline; other allosteric
characteristics observed include sigmoidal substrate variation and
inhibition plots of activity. The membrane fraction and a low molecular
weight compound in...
An enzyme system from cell-free yeast homogenates mediating the
transfer of the methyl group from S-adenosylmethionine-methyl-C¹⁴
or methionine-methyl-C¹⁴ to C-28 of ergosterol has been studied.
The effects of divalent cations, suithydryl inhibitors and reducing
substances on the activity of the enzyme system have been investigated.
It was established that for...
The terminal reactions in the biosynthetic pathway of methionine
in Saccharomyces cerevisiae were investigated in this study. Analyses
of a number of methionine auxotrophs for biochemical deficiences
established four mutant groups. It was observed from qualitative feeding
experiments that some auxotrophs were able to utilize S-adenosylmethionine
(AM) and S-adenosyl-homocysteine (AH)...
The mechanism of transsulfuration and the role of cystathionine
in the biosynthesis of methionine in yeast were investigated.
Saccharomyces were shown to accumulate cystathionine by use
of the ³⁵S labeled compound.
Cell-free extracts of the wildtype clone as well as methionine
auxotrophs were shown to cleave cystathionine. The enzymatically
Studies were carried out to elucidate the mechanism of enzymatic
control of methionine biosynthesis in Saccharomyces cerevisiae.
Enzymatic studies demonstrated that, in addition to the methionine
activating enzyme, the S-adenosylmethionine:homocysteine
transmethylase enzyme was induced during cultivation in the presence
of excess methionine. A similar, though reduced effect was
An attempt has been made to elucidate the biosynthetic precursor
of ethylene in the mold P. digitatum. By application of basic
radiotracer methodology and the utilization of several specifically
labeled radiochemical substrates, it has been possible to demonstrate
that the internal carbon atoms of C-4 dicarboxylic acids such