Many different species of acidophilic prokaryotes, widely distributed within the domains Bacteria and Archaea, can catalyze the dissimilatory oxidation of ferrous iron or reduction of ferric iron, or can do both. Microbially mediated cycling of iron in extremely acidic environments (pH < 3) is strongly influenced by the enhanced chemical stability of ferrous iron and far greater solubility of f...

There are five main groups of microorganisms that participate in fermenting cocoa: filamentous fungi, yeasts, lactic acid bacteria, acetic acid bacteria, and various Bacillus species [1]. Fungi, yeasts, lactic acid bacteria, and acetic acid bacteria are active mainly in the first stage (from 0 to 48h). Yeasts convert sugar from the mucilage of cocoa beans into alcohol, and break the pectin down...

The reactive oxidizing species in the selective oxidation of methane to methanol in oxygen activated Cu-ZSM-5 was recently defined to be a bent mono(μ-oxo)dicopper(II) species, [Cu(2)O](2+). In this communication we report the formation of an O(2)-precursor of this reactive site with an associated absorption band at 29,000 cm(-1). Laser excitation into this absorption feature yields a resonance...

More than 100 million individuals worldwide are exposed to arsenic-contaminated water, making the investigation of arsenic mobility in aquatic systems of utmost importance. Iron (hydr)oxides play a key role in preventing arsenic release in aquifers and soils due to their strong arsenic sorption and are even used to remove arsenic in water treatment. Neutrophilic Fe(II)-oxidizing bacteria produc...

DsbA, a 21-kDa protein from Escherichia coli, is a potent oxidizing disulfide catalyst required for disulfide bond formation in secreted proteins. The active site of DsbA is similar to that of mammalian protein disulfide isomerases, and includes a reversible disulfide bond formed from cysteines separated by two residues (Cys30-Pro31-His32-Cys33). Unlike most protein disulfides, the active-site ...

Mitochondria were prepared from roots, stalks, leaves, and leaf veins of spinach. The mitochondrial preparations were examined for their ability to oxidize glycine via the respiratory chain. It is shown that the glycine-oxidizing capacity is restricted to photosynthetically active tissue. The activity is present in mitochondria from the green parts of the leaves, but not in mitochondria from ro...

in this study, methanol and ether extracts of five endemic asperula species (rubiaceae) from turkey (a. antalyensis, a. brevifolia, a. pseudochlorantha, a. purpurea subsp. apiculata and a. serotina), used in the traditional system of medicine, were tested for antimicrobial activity by the agar well diffusion method and the broth dilution method. the most active species were asperula brevifolia ...

An abundance of hydrocarbon oxidizing microbes is found, not unexpectedly, in areas where extraordinary quantities of hydrocarbons exist in the biosphere. In particular, bacteria of the genus Mycobacterium develop in areas of oil and gas production and in areas of petroliferous gas seeps. One of these species, Mycobacterium paraffinicum n. sp., shows a high degree of specificity for petroleum h...