We measured the uptake rate of molybdatc and related kinetic parameters for nine taxa of cyanobacteria and for the natural phytoplankton communities of six freshwater lakes containing planktonic Nz-fixing cyanobacteria. Molybdate uptake followed saturation kinetics and was competitively inhibited by both tungstate and sulfate. Tungstate inhibited molybdate uptake in a nearly mole-for-mole fashi...

A simply and facilely synthesized MoO3 solution was developed to fabricate charge injection layers for improving the charge-injection properties in p-type organic field-effect transistors (OFETs). By dissolving MoO3 powder in ammonium (NH3) solvent under air atmosphere, an intermediate ammonium molybdate ((NH4)2MoO4) precursor is made stable, transparent and to be spin-coated to form the MoO3 i...

Although retinoic acid (RA) teratogenicity has been investigated for decades, the mechanisms underlying RA-induced outflow tract (OFT) malformations are not understood. Here, we show zebrafish embryos deficient for Cyp26a1 and Cyp26c1 enzymes, which promote RA degradation, have OFT defects resulting from two mechanisms: first, a failure of second heart field (SHF) progenitors to join the OFT, i...

When Escherichia coli was grown in the presence of tungstate, inactive forms of two molybdoenzymes, nitrate reductase and formate dehydrogenase, accumulated and were converted to their active forms upon incubation of cell suspensions with molybdate and chloramphenicol. The conversion to the active enzymes did not occur in cell extracts. When incubated with [(99)Mo]molybdate and chloramphenicol,...

Clearly there are differences in the observed reactivities of the "heavily oxidized" surfaces of Mo(1 I0) prepared by Queeney et al. [1] and those prepared by us [2]. We note, however, that our study is in agreement with, and provides fresh insight into, the chemistry of high surface-area (HSA), "real-world" molybdate catalysts. The 3D oxide prepared by us (i) does not produce methyl radicals, ...

Anabaena variabilis fixes nitrogen under aerobic growth conditions in differentiated cells called heterocysts using either a Mo nitrogenase or a V nitrogenase. The nifH1 gene, which encodes the dinitrogenase reductase of the Mo nitrogenase that is expressed only in heterocysts, is cotranscribed with nifD1 and nifK1, which together encode the Mo dinitrogenase. These genes were expressed in the p...

Abstract Organic esters of phosphoric acid and other organophosphorous compounds are enzymatically hydrolyzed during wastewater treatment by microbial phosphoesterases, especially phosphomonoesterase (phosphatase). For physiological reasons, the enzyme is inhibited its main inorganic reaction product, ortho-phosphate. It known that oxyanions transition metals, resembling molecular topology orth...