John B. Smart

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The effect of P nutrition on phosphate uptake and alkaline phosphatase activity was studied in chemostat culture for four rhizobial and three bradyrhizobial species. Phosphate-limited cells took up phosphate 10- to 180-fold faster than phosphate-rich cells. The four fast-growing rhizobial strains contained high levels of alkaline phosphatase activity under(More)
Pyruvate kinase from Propionibacterium shermanii was shown to be activated by glucose-6-phosphate (G-6-P) at non-saturating phosphoenol pyruvate (PEP) concentrations but other glycolytic and hexose monophosphate pathway intermediates and AMP were without effect. Half-maximal activation was obtained at 1 mM G-6-P. The presence of G-6-P decreased both the(More)
With continuous cultures in a fully defined minimal salts medium steady states were achieved at both limiting and non-limiting concentrations of phosphate in the inflowing medium for Rhizobium trifolii WU95, cowpea Rhizobium NGR234, and Bradyrhizobium CB756. Millimolar growth yields obtained from P-limited cultures varied over 2-fold from 3.2 g dry(More)
The concentrations of glycolytic intermediates and ATP and the activities of certain glycolytic and gluconeogenic enzymes were determined in Propionibacterium shermanii cultures grown on a fully defined medium with glucose, glycerol or lactate as energy source. On all three energy sources, enzyme activities were similar and pyruvate kinase was considerably(More)
The β-galactosidase from Streptococcus thermophilus formed transferase products (including up to six disaccharides and two trisaccharides) during the hydrolysis of lactose to glucose and galactose. The extent of transferase products formed was dependent on the initial lactose concentration, reaching up to 40% of the total carbohydrate at 70% w/v lactose. At(More)
The distribution of chromogranin/secretogranin (Cg/Sg) mRNAs, determined by Northern and in situ hybridization, was analyzed in 14 cultured pituitary adenomas characterized by immunohistochemistry and hormone secretion in a defined medium in vitro. There were 5 functional GH adenomas, 1 silent GH adenoma, 7 null cell adenomas, and 1 oncocytoma. The null(More)
Many environmental carcinogens gain access to the body only after traversing a mucosal surface. Due to their small size, most carcinogens are not recognized by the immune system and pass unhindered from the external to the internal environment. In previous studies, we demonstrated that secretory IgA directed against the carcinogen 2-acetylaminofluorene(More)
Strains of Clostridium acetobutylicum were tested for the presence of β-galactosidase and phospho-β-galactosidase activities when grown on lactose. All strains, except C. acetobutylicum ATCC 824, showed both enzyme activities. Only phospho-β-galactosidase activity was detected with C. acetobutylicum ATCC 824. C. acetobutylicum strains P262 and ATCC 824(More)
Chromogranin-A-positive pituitary adenomas include glycoprotein hormone-producing adenomas, null cell adenomas, and a few other pituitary adenomas. We studied the effects of GnRH, CRF, dexamethasone, and phorbol 12-myristate 13-acetate on FSH and LH secretion and on FSH beta and chromogranin-A and -B mRNA expression in 10 chromogranin-A-positive adenomas in(More)
Lysozyme/EDTA treatment of four fast-growing rhizobia released repeatable protein profiles after polyacrylamide slab gel electrophoresis. Similar treatment of slow-growing rhizobia failed to release such periplasmic proteins. For the four-fast-growing rhizobia, both P-repressible and P-inducible protein bands occurred. The only P-repressible protein(More)
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