Search

The chlorobenzene dioxygenase from Pseudomonas sp. strain P51 converts substituted aromatic compounds to the S configuration at the carbon atom. The enantiomeric excess was higher than the same reaction catalyzed by toluene dioxygenases. This is of interest to the biotechnology industry because cis-dihydrodiols are building blocks for molecules with multiple chiral centers.

Research has been conducted on the Pseudomonas strains that utilize m-toluate. The results of the isolation of these strains from the oil-contaminated soil samples in Belarus are discussed.

Pseudomonas sp. strain P51 cis-chlorobenzene dihydrodiol dehydrogenase (CDD)(TcbB) expressed in Escherichia coli DH5alpha (pTCB149) has been found to catalyze enantioselective dehydrogenase reactions. The study was carried out with the object of investigating the potential of CDD for enantiomeric resolution of chiral dihydrodiols. CDD preferentially oxidized the para-halogenated cis-toluene dihydrodiol enantiomers preferentially formed by chlorobenzene dioxygenase (CDO).

Various microbial isolation and genetic techniques were used to determine whether chlorobenzene (CB) metabolism is a natural microbial response to contamination with synthetic chemicals. Results indicate that the ability to degrade CB is not an inherent property, but one which has evolved. The evolution is a result of simple horizontal gene transfer and gene recombination between different ancestral strains.

A study was conducted to examine low-frequency horizontal transfers of chlorocatechol degradative genes from Pseudomonas sp. strain B13 in activated-sludge microcosms. Matings were carried out with cultures pre-grown on Luria-Bertani medium that was washed and resuspended in Z3 mineral medium. The microcosms were characterized by glass reactors and operated at a volume of about 05. liter of culture medium.

An Escherichia coli whole-cell biosensor was developed for linear alkane detection through the transcriptional fusion of Vibrio harveji promotorless luxAB genes and Pseudomonas oleovorans alkB promoter. Standardized and optimized assays were then employed in evaluating the biosensor strain's ability to detect octane concentrations. The biosensor was also found to be useful in estimating linear akane concentrations in groundwater samples contaminated with oil.

Research has been conducted on partial nitrification of ammonium to nitrite under oxic conditions. The authors have investigated the role of pH, low temperature and dilution rate in the formation, composition and activity of ammonia-oxidizing biomass in bioreactors from sewage sludge.