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The gene encoding OprF, a major outer membrane protein in Pseudomonas species, was believed to be constitutively transcribed from a single sigma 70 promoter immediately upstream of the gene. A novel putative extracytoplasmic function (ECF) sigma factor gene, sigX, located immediately upstream of oprF was found in both Pseudomonas aeruginosa PAO1 and Pseudomonas fluorescens OE 28.3. It was observed that SigX is involved in the regulation of other genes in P. aeruginosa.

A sequence analysis utilizing the bacterial strains and growth conditions of Escherichia coli was conducted to pFAJ26000, a small replicon of a complete nucleotide sequence 5936 bp. Replication of genes in pFAJ2600 showed that deduced proteins RepA and RepB are related to similarly organized genes in a number of cryptic plasmids from various actino-mycetes. The plasmid was also known to carry encoding putative member of the plasmid multimer resolution protein. Furthermore, the sequence analysis of pFAJ2600 showed that some of its regions are unnecessary for stable maintenance in Rhodococcus.

A study was conducted on the three copies of the element IS1415 found in Rhodococcus erythropolis NI86/21. These copies are members of the IS21 family isolated from an actinomycte and adjacent to one of which is a 47-bp sequence very similar to the conserved 5' end of integrons. Results show that the IS1415 with a chloramphenicol resistance gene is accurately transposed after delivery from a suicide vector to Rhodococcus erythropolis SQ1.

The gene encoding the ThcF protein was cloned and sequenced from Rhodococcus erythropolis NI86/21 to determine the mechanisms that mediate the biodegradation of thiocarbamates. The thcF gene encoding the thiocarbamate-inducible protein F exhibited high GC content with a molecular mass of 29,664 kDa. The ThcF protein of the noncardioform Rhodococcus erythropolis also exhibited a protein sequence that was homologous to nonheme haloperoxidase.

Analysis of the N-terminal sequences of two EPTC (S-ethyl dipropylcarbamothioate)-activated proteins from Rhodococcus sp. strain NI86 21 using two-dimensional electrophoresis helps localize the NAD+-dependent dehydrogenase and cytochrome P-450 structural genes on two specific DNA fragments. Hybridization experiments reveal that the aldehyde dehydrogenase gene is present in all strains of Rhodococcus genus while the cytochrome P-450 system is restricted to the Rhodococcus sp. strain NI86 21. Complementation experiments using the acceptor strains of EPTC-negative Rhodococcus erythropolis SQ 1 and mutant FAJ2027 confirm the participation of cytochrome P-450 system in herbicide biosafening and EPTC degradation.

N-terminal sequence analysis of Pseudomonas fluorescens reveals a surface exposed site for the proline-rich region of major outer membrane protein OprF and regions in carboxy half that are exposed but less accessible. The proline-rich domain is the most conserved region of the different P. fluorescens OprFs. Carboxy half of the OprF contains a sequence motif well conserved in enterobacterial OmpA protein.

The cloning and sequencing of the recA gene from Pseudomonas fluorescens OE 28.3 were described. DNA sequence analysis showed that the coding region of the P. fluorescens gene, specifying a protein of 352 amino acids, was preceded by an SOS box. The deduced amino acid sequence is highly similar to the RecA proteinsfrom Pseudomonas aeruginosa and Azotobacter vinelandii. In addition, a recA mutant was constructed and characterized. This mutant exhibited an increased sensitivity to UV irradiation and methyl methanesulphonate, and was severely impaired in performing homologous recombination.

A gene cluster is identified that has encoded the enzymes and regulatory and transporter proteins for the different steps in the biosynthesis of extracellular polysaccharides (EPS) of the probiotic strain Lactobacillus rhamnosus GG. The characterization of the welE mutant has shown that deprivation of the long, galactose-rich EPS molecules has resulted in an increased adherence and biofilm formation capacity of Lactobacillus rhamnosus GG, because of less shielding of adhesins such as fimbria-like structures.

Research has been conducted on Pseudomonas sp. strain BW11M1 isolate which produces antibacterial compound active against P. putida GR12-2R3. Results demonstrate that this compound is putidacin, and the cloning and characterization of the gene encoding this putidacin are described.

Research has been conducted on Streptomyces coelicolor A3(2) proteasome-lacking mutant. The study of the mutant's intracellular enzyme with chymotrypsin-like activity absent from the wild type is described.