Amphiploids (2n = 6x = 42) of Ae. kotschyi and Ae. biuncialis with self-compatible S. cereale were produced from F1 sterile hybrids (2n = 3x = 21) through colchicine treatment and callus tissue regeneration. The amphiploids resembled the F1 plants in overall morphology, but were larger in all respects and self-fertile. The spikelets consisted mostly of 3 well-developed florets. Selfed seeds wer...

A previous phenotypic screen by GSK identified 2-(quinolin-4-yloxy)acetamides as potent growth inhibitors of Mycobacterium tuberculosis (Mtb). We report the results of a preliminary structure–activity relationship (SAR) study of the compound class which has yielded more potent inhibitors. An Mtb cytochrome bd oxidase deletion mutant (cydKO) was found to be hypersensitive to most members of the ...

The mode of membrane attachment of the Rieske iron-sulfur proteins from cytochrome b6f complex of pea thylakoids and from cytochrome bc1 complex of yeast mitochondria has been studied using biochemical approaches. The relative sensitivity of the Rieske protein to trypsin in the thylakoid membrane shows that all trypsin sites of the Rieske protein are on the lumen side of the thylakoid membrane....

Electronic connection between Qo and Qi quinone catalytic sites of dimeric cytochrome bc1 is a central feature of the energy-conserving Q cycle. While both the intra- and inter-monomer electron transfers were shown to connect the sites in the enzyme, mechanistic and physiological significance of the latter remains unclear. Here, using a series of mutated hybrid cytochrome bc1-like complexes, we...

Functional and ultrastructural studies have indicated that the components of the photosynthetic apparatus of Rhodobacter sphaeroides are highly organized. This organization favors rapid electron transfer that is unimpeded by reactant diffusion. The light-harvesting complexes only partially surround the photochemical reaction center, which ensures an efficient shuttling of quinones between the p...

Rieske iron-sulfur (2Fe-2S) clusters play a central role in energy transduction by the quinone:cytochrome c oxidoreductases of the respiratory and photosynthetic chains (the bc1 and b6f complexes) and in the bacterial degradation of aromatic compounds.1 Distinguished from “ferredoxin-type” 2Fe-2S clusters by reduction potentials up to 700 mV higher, Rieske centers have one iron atom coordinated...

BACKGROUND Research in adult populations has highlighted sex differences in cortisol concentrations and laboratory pain responses, with men exhibiting higher cortisol concentrations and reduced pain responses compared with women. Yet, less is known about the relationship of cortisol concentrations to pain in children. OBJECTIVE This study examined associations between sex, cortisol, and pain ...

The ubiquinol-cytochrome c oxidoreductase (bc1 complex), also denoted complex III of the respiratory chain, is present in the inner mitochondrial membrane of eukaryotic organisms and many aerobic bacteria. It catalyzes electron transfer from ubiquinol to cytochrome c coupled to the electrogenic translocation of protons across the membrane. The proton electrochemical gradient thus generated is u...