When nitrate is used in a biological electron transport
system as the final acceptor of hydrogen to form water,
the system is characterized as "Nitrate Respiration." However,
the quantitative expression of the over-all participation
of NO₃⁻(0) in the oxidation of glucose by denitrifiers
such as Pseudomonas stutzeri deserves clarification.
In...
Methods examined for the preparation of cells from tissues of salmonid fishes for primary cultivation were the fragment (explant) and enzyme dispersion techniques. Both methods were employed for the cultivation of a variety of tissues from Pacific salmon, Oncorhynchus spp., and the steelhead trout, Salmo gairdneri gairdneri. A technique was...
Prevailing concepts relating to the non-enzymatic gaseous
loss of nitrite from soil are thought to be inadequate as regards
to the mechanisms involved. The conventional explanation for
nitric oxide formation i.e., the acid decomposition of nitrite,
is held to be insufficient in substrates of only mild or slight
acidity. A...
Chemical and microbial analyses were made at four seasonal intervals on soil horizons under red alder, conifers, and mixed
alder-conifers at the Cascade Head Experimental Forest, established in 1937 by the U. S. Forest Service near Otis, Oregon.
Microbial analyses showed that although plate counts of molds and bacteria fluctuated...
The dairy industry relies primarily on consistent acid production
by the lactic streptococci for the manufacture of certain cheeses
and fermented dairy products. Variation in these cultures due to
genetic exchange has not been thoroughly investigated. This study
was undertaken to determine if genetic homology exists within the lactic
group,...
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)...
An enzyme system was prepared from Saccharomyces cerevisiae,
strain MCC, which carries out the transfer of the methyl group from
S-adenosylmethionine or methionine to the side chain of yeast sterols.
The cell-free system has been shown to be incapable of synthesizing
ergosterol but carries out the synthesis of two as...
An ecological study of a microorganism similar to that isolated
in 1956 and designated as Micrococcus radiodurans indicated
that the organism could be isolated from several different environments.
By taking advantage of its radio-resistivity, high levels of
gamma radiation were used in the isolation procedures to inactivate
most of the...
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
produced...