Pathways of proton entry have been identified in the proton-translocating heme-copper oxidases, but the proton exit pathway is unknown. Here we report experiments with cytochrome bo3 in Escherichia coli cells that may identify the beginning of the exit pathway. Systematic mutations of arginines 438 and 439 (R481 and R482 in the E. coli enzyme), numbering as in cytochrome aa3 from bovine heart m...

Myxobacteria of marine origin are rare and hard-to-culture microorganisms, but they genetically harbor high potential to produce novel antibiotics. An extensive investigation on the secondary metabolome of the unique marine myxobacterium Haliangium ochraceum SMP-2 led to the isolation of a new polyketide-nonribosomal peptide hybrid product, haliamide (1). Its structure was elucidated by spectro...

The effect of gold presence on carbon monoxide oxidation and ethanol steam reforming catalytic behavior of two Ce-Zr-Co mixed oxides catalysts with a constant Co charge and different Ce/Zr ratios was investigated. The Ce-Zr-Co mixed oxides were obtained by the pseudo sol-gel like method, based on metallic propionates polymerization and thermal decomposition, whereas the gold-supported Ce-Zr-Co ...

It is well known that isotopic tracer st,udies of a complex system of interrelated reactions can determine the existence and magnitude of reaction sequences for transferring atoms from a given reactant to a particular product and also in many cases, usually through studies involving asymmetrically labeled reactants and including degradation of the products, establish parameters with which postu...

The heme propionates of heme peptide 1-25 from horse heart cytochrome c were methylated in acidified methanol. The methylated heme peptide combines with apocytochrome c in a single second order kinetic phase whose rate constant is within a factor of four of that measured for the unmethylated heme peptide. The dissociation constants for the two complexes are also within a factor of four. The met...

-We have studied the mesomorphism of p-acryloyland p-methacryloy1-oxy-p'substituted azoand azoxybenzenes. Polymers, obtained by free radical polymerization of these compounds in solution, give anisotropic melts at T,. According tox-ray diffraction data the polymers are characterized by a smectic structure. There is no correlation between the thermal behaviour of monomers and polymers. The optic...

In the centrosymmetric binuclear title complex, [Tb(2)(C(9)H(9)O(3))(6)(C(12)H(8)N(2))(2)], the two Tb(III) ions are linked by four 2-phen-oxy-propionate (L) groups through their bi- and tridentate bridging modes. Each Tb(III) ion is nine-coordinated by one 1,10-phenanthroline mol-ecule, one bidentate carboxyl-ate group and four bridging carboxyl-ate groups in a distorted TbN(2)O(7) monocapped ...

In the title compound, [UO(2)(C(4)H(7)O(3))(2)](n), the dioxouranium(VI) units are linked by 2-hydr-oxy-2-methyl-propionate ligands into a honeycomb structure. The U atom is seven-coordinate in a penta-gonal-bipyramidal geometry. The uncoordinated hydr-oxy groups of the 2-hydr-oxy-2-methyl-propionate ions inter-act with the O atom of the uranyl and with the coordinated hydr-oxy group of an adja...