Environmental properties and aquatic hazard assessment of anionic surfactants: physico-chemical, environmental fate and ecotoxicity properties.

This paper summarizes the environmental hazard assessment of physicochemical properties, environmental fate and behavior and the ecotoxicity of a category of 61 anionic surfactants (ANS), comprised of alkyl sulfates (AS), primary alkane sulfonates (PAS) and alpha-olefin sulfonates (AOS) under the High Production Volume Chemicals Program of the Organisation for Economic Co-operation and Development (OECD). The most important common structural feature of the category members examined here is the presence of a predominantly linear aliphatic hydrocarbon chain with a polar sulfate or sulfonate group, neutralized with a counter-ion. The hydrophobic hydrocarbon chain (with a length between C(8) and C(18)) and the polar sulfate or sulfonate groups confer surfactant properties and enable the commercial use of these substances as anionic surfactants.

Toxicological properties and risk assessment of the anionic surfactants category: Alkyl sulfates, primary alkane sulfonates, and α-olefin sulfonates.

The category of the anionic surfactants (ANS) consisting of 46 alkyl sulfates, 6 primary alkane sulfonates, and 9 α-olefin sulfonates has been assessed under the high production volume (HPV) chemicals program of the Organisation for Economic Cooperation and Development (OECD) in 2007. In this review the toxicological properties of these chemicals are summarized. The chemicals of this category are used predominantly in detergents, household cleaning products, and cosmetics.

Environmental properties of long-chain alcohols. Part 2: Structure-activity relationship for chronic aquatic toxicity of long-chain alcohols.

Daphnia magna reproduction tests were performed with C(10), C(12), C(14) and C(15) alcohols to establish a structure-activity relationship of chronic effects of long-chain alcohols. The data generation involved substantial methodological efforts due to the exceptionally rapid biodegradability of the test substances and the need to test as close as possible to their water solubility limits. Test concentrations were determined by GC-MS before and after test solution renewal.

An outer membrane protein (OmpA) of Escherichia coli K-12 undergoes a conformational change during export.

Pulse-chase experiments were performed to follow the export of the Escherichia coli outer membrane protein OmpA. Besides the pro-OmpA protein, which carries a 21-residue signal sequence, three species of ompA gene products were distinguishable. One probably represented an incomplete nascent chain, another the mature protein in the outer membrane, and the third, designated imp-OmpA (immature processed), a protein which was already processed but apparently was still associated with the plasma membrane.

Rate of translation and kinetics of processing of newly synthesized molecules of two major outer-membrane proteins, the OmpA and OmpF proteins, of Escherichia coli K12.

The rate of synthesis of the OmpA and OmpF proteins, two of the major outer membrane proteins of Escherichia coli K12, was determined. At 25 degrees C both proteins were translated at 6.5 amino acids/s, and the OmpF protein was translated at 15 amino acids/s at 37 degrees C.

Precursor proteins are intermediates in vivo in the synthesis of two major outer membrane proteins, the OmpA and OmpF proteins, of Escherichia coli K12.

The OmpA and OmpF proteins are major outer membrane proteins of Escherichia coli K12. Their precursors, the pro-OmpA and pro-OmpF proteins, have been detected in vivo in pulse-labelling experiments carried out with [35S]methionine at 25 degrees C. Wehn the pulse was at 37 degrees C, however, no precursors were detected.

Major proteins of the outer cell envelope membrane of Escherichia coli K12: multiple species of protein I differ in primary structure.

Protein I, one of the major outer membrane proteins of E. coli in most K12 strains is represented by two very similar polypeptides Ia and Ib. Sequential mutations (involving selections for phage resistance) can lead to loss of proteins Ia and Ib.