The isotope studies of Strassman et al. (3, 4) first implicated cu-acetolactate and cu-aceto-cY-hydroxybutyrate as biosynthetic precursors of valine and isoleucine, respectively. The observed accumulation of acetolactate by Escherichia coli (5, 6) and of the decarboxylation products of acetolactate and acetohydroxybutyrate by Neurospora crassa (7) when mutants of these organisms are grown with ...

We report the first observation of infrared (IR) and mass spectra of neutral, aliphatic amino acid clusters: the example presented herein is for (valine)(n), n = 2-5. The clusters are generated in a supersonic expansion and their IR spectra are recorded in various fragment and (valine)(n-1)H(+) (n = 2-5) mass channels. The ions are created by single photon ionization with a VUV laser at 118 nm ...

Acetohydroxy acid synthase (AHAS), which catalyzes the key reactions in the biosynthesis pathways of branched-chain amino acids (valine, isoleucine, and leucine), is regulated by the end products of these pathways. The whole Corynebacterium glutamicum ilvBNC operon, coding for acetohydroxy acid synthase (ilvBN) and aceto hydroxy acid isomeroreductase (ilvC), was cloned in the newly constructed ...

A decreased serum level of branched-chain amino acid (BCAA) is a distinctive metabolic disorder in patients with liver cirrhosis. Recently, BCAA has been reported to exert various pharmacological activities, and valine, which is a BCAA, has been shown to affect lipid metabolism and the immune system in in vivo experiments. However, the clinical impact of valine supplementation on viral hepatiti...

1. Threonine deaminase has been purified about 1400fold from extracts of the photosynthetic bacterium Rhodopseudomonas spheroides by ammonium sulfate fractionation and by chromatography on DEAE-cellulose and hydroxylapatite columns. The purified enzyme is almost completely resolved with respect to bound coenzyme, and the activity of holoenzyme is specific for pyridoxal phosphate. The enzyme is ...

Katz, Edward (Rutgers, The State University, New Brunswick, N. J.), Clarence R. Waldron, and Mary Lou Meloni. Role of valine and isoleucine as regulators of actinomycin peptide formation by Streptomyces chrysomallus. J. Bacteriol. 82:600-608. 1961-d-Valine is an effective inhibitor of actinomycin synthesis by Streptomyces chrysomallus; l-valine stimulates actinomycin production and reverses the...

The ability of the follicle-associated epithelium (FAE) of rat Peyer's patch to accumulate valine has been measured using a new technique of autoradiographic analysis. Maximum uptake of valine was achieved by enterocytes present in the dome region of the FAE. Valine uptake was not seen in enterocytes present on the lower slopes of the FAE or in follicle-associated crypts. The ability of the FAE...