The regulation of CO(2) assimilation by intact spinach (Spinacia oleracea) chloroplasts by exogenous NADP-linked nonreversible d-glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.9) was investigated. This dehydrogenase mediated a glyceraldehyde 3-phosphate/glycerate 3-phosphate shuttle for the indirect transfer of NADPH from chloroplast to the external medium. The rate of NADPH formation in th...

Detection of phosphate using amperometry was investigated. The phosphomolybdate complex, formed by addition of nitric acid, ammonium molybdate and phosphate, was reduced at a carbon paste electrode polarised at +0.3V (versus Ag/AgCl). The major characteristics observed were simplicity of the equipment, a limited consumption of reagents and a low detection limit (0.3mumoll(-1)), with a linear ra...

In soil, bioavailable inorganic orthophosphate is found at low concentrations and thus limits biological growth. To overcome this phosphorus scarcity, plants and bacteria secrete numerous enzymes, namely acid and alkaline phosphatases, which cleave orthophosphate from various organic phosphorus substrates. Using profile hidden Markov modeling approaches, we investigated the abundance of various...

The effects of kinetin on starch and sugar levels and on (14)CO(2) and (32)P-orthophosphate labeling patterns of floated Chinese cabbage (Brassica pekinensis) leaf discs were investigated. Kinetin caused gross starch degradation. Neutral sugars were depressed by 30 to 40% in leaf tissue treated with kinetin for 24 hours. (14)CO(2) labeling of leaf discs pretreated with kinetin for 24 hours show...

Alkaline phosphatase from Escherichia coli catalyzes the hydrolysis of S-substituted monoesters of phosphorothioic acid of the type RSP03Naz (R = -CH2CH2NH2,-CH2CHzNHCOCH3,-CH,COOH, or -CH2CHzCOOCzH~), at the S-P bond, to yield orthophosphate and the corresponding thioalcohols. The rate of enzymic hydrolysis of cysteamine S-phosphate was measured at different pH values and substrate concentrati...

A high-throughput screening was developed for the detection of phosphatase activity in bacterial colonies. Unlike other methods, the current procedure can be applied to any phosphatase because it uses physiological substrates and detects the compelled product of all phosphatase reactions, that is, orthophosphate. In this method, substrates diffuse from a filter paper across a nitrocellulose mem...

The phospholipids of cultured parsley and soybean cells were labelled with myo-[2-3H]inositol, [2-3H]glycerol or [32P]orthophosphate. By oneand two-dimensional chromatographic compari­ son of the labelled phospholipids with reference substances, the presence of l-(3-sn-phosphatidyl)-D-myo-inositol 4-phosphate and l-(3-sn-phosphatidyl)-D-myo-inositol 4,5-bisphosphate was demonstrated in these cu...

* For DPN synthesis, 1.0 ml. of reaction mixture contained 50 y of the enzyme preparation, 0.3 micromole of MgCl 2, and 50 micromoles of glycylglycine buffer (pH 7.4) in addition to ATP and NMN; for ATP synthesis 1.0 ml. contained 50 y of the enzyme preparation, 0.75 micromole,of MgC12, and 50 micromoles of glycylglycine buffer (pH 7.4) in addition to DPN and P-P. Constant values were reached a...

Anthropogenic activities (e.g., rural urbanization) play major roles in preventing the achievement of sustainable water quality, where eutrophication—the exacerbation increase nutrient concentrations combined with warmer temperatures and lower light availability, leading to dense growth plant life depleting amount available oxygen killing aquatic life—remains a challenge for surface bodies. Fil...

Bacteria able to use at least one of 13 ionic alkylphosphonates of O-alkyl or O,O-dialkyl alkylphosphonates as phosphorus sources were isolated from sewage and soil. Four of these isolates used 2-aminoethylphosphonic acid (AEP) as a sole carbon, nitrogen, and phosphorus source. None of the other phosphonates served as a carbon source for the organisms. One isolate, identified as Pseudomonas put...