Evolutionary and functional history of the Escherichia coli K1 capsule.

Escherichia coli is a leading cause of invasive bacterial infections in humans. Capsule polysaccharide has an important role in bacterial pathogenesis, and the K1 capsule has been firmly established as one of the most potent capsule types in E. coli through its association with severe infections.

Efficient Protein Digestion at Elevated Temperature in the Presence of Sodium Dodecyl Sulfate and Calcium Ions for Membrane Proteomics.

The growing significance of membrane proteins inspires continuous development and improvement of methods for robust membrane proteomics. Here, we developed a very simple and efficient method for membrane protein digestion using an ionic detergent, sodium dodecyl sulfate (SDS), at high temperature, conditions where trypsin is normally inactivated. Our results suggest that trypsin can be stabilized by a combination of calcium ions and sodium chloride, which enables protein digestion at elevated temperature in the presence of strong ionic detergents such as SDS.

Complement Susceptibility in Relation to Genome Sequence of Recent Klebsiella pneumoniae Isolates from Thai Hospitals.

The capacity to resist the bactericidal action of complement (C') is a strong but poorly understood virulence trait in spp. Killing requires activation of one or more C' pathways, assembly of C5b-9 membrane attack complexes (MACs) on the surface of the outer membrane (OM), and penetration of MACs into the target bilayer. We interrogated whole-genome sequences of 164 isolates from three tertiary hospitals in Thailand for genes encoding surface-located macromolecules considered to play a role in determination of C' resistance.

Genetic Techniques for Manipulation of the Phytosterol Biotransformation Strain Mycobacterium neoaurum NRRL B-3805.

Mycobacterium neoaurum is a saprophytic, soil-dwelling bacterium. The strain NRRL B-3805 converts phytosterols to androst-4-ene-3,17-dione (androstenedione; AD), a precursor of multiple C19 steroids of importance to industry. NRRL B-3805 itself is able to convert AD to other steroid products, including testosterone (Ts) and androst-1,4-diene-3,17-dione (androstadienedione; ADD).

Development of an In Vitro Assay for Detection of Drug-Induced Resuscitation-Promoting-Factor-Dependent Mycobacteria.

Tuberculosis is a major infectious disease that requires prolonged chemotherapy with a combination of four drugs. Here we present data suggesting that treatment of Mycobacterium tuberculosis, the causative agent of tuberculosis, and Mycobacterium smegmatis, a model organism widely used for the screening of antituberculosis agents, with first-line drugs resulted in the generation of substantial populations that could be recovered only by the addition of a culture supernatant from growing mycobacteria. These bacilli failed to grow in standard media, resulting in significant underestimation of the numbers of viable mycobacteria in treated samples.

Recognition of Membrane Sterols by Polyene Antifungals Amphotericin B and Natamycin, A (13)C MAS NMR Study.

The molecular action of polyene macrolides with antifungal activity, amphotericin B and natamycin, involves recognition of sterols in membranes. Physicochemical and functional studies have contributed details to understanding the interactions between amphotericin B and ergosterol and, to a lesser extent, with cholesterol. Fewer molecular details are available on interactions between natamycin with sterols.

The external PASTA domain of the essential serine/threonine protein kinase PknB regulates mycobacterial growth.

PknB is an essential serine/threonine protein kinase required for mycobacterial cell division and cell-wall biosynthesis. Here we demonstrate that overexpression of the external PknB_PASTA domain in mycobacteria results in delayed regrowth, accumulation of elongated bacteria and increased sensitivity to β-lactam antibiotics. These changes are accompanied by altered production of certain enzymes involved in cell-wall biosynthesis as revealed by proteomics studies.

Population, environment, medicine and global sustainability.

The final two decades of this century see our planet in a highly perilous condition. This paper, after touching on the problem of nuclear proliferation, goes on to consider three other issues overpopulation, environmental depredation and the future of medical practice all of which are of high salience. The section on population concentrates on the time required for numbers to stabilize at two children per family.