title: Cis-trans isomerase gene in psychrophilic Pseudomonas syringae is constitutively expressed during growth and under conditions of temperature and solvent stress.
abstract: In a recent study, we established that psychrophilic Pseudomonas syringae (Lz4W) requires trans-monounsaturated fatty acid for growth at higher temperatures (Kiran et al. in Extremophiles, 2004). It was also demonstrated that the cti gene was highly conserved and exhibited high sequence identity with cti of other Pseudomonas spp. (Kiran et al. in Extremophiles, 2004). Therefore it would be interesting to understand the expression of the cti gene so as to unravel the molecular basis of adaptation of microorganisms to high temperature. In the present study, the expression of cti was monitored by RT-PCR analysis during different growth stages and under conditions of high temperature and solvent stress in P. syringae. Results indicated that the cti gene is constitutively expressed during different stages of growth and the transcript level is unaltered even under conditions of temperature and solvent stress implying that the observed increase in trans-monounsaturated fatty acids (Kiran et al. in Extremophiles, 2004) is not under transcriptional control. A putative promoter present in the intergenic region of the metH and cti gene has also been characterized. The translation start site ATG, the Shine-Dalgarno sequence AGGA and the transcription start site "C" were also identified. These results provide evidence for the first time that the cti gene is constitutively expressed under normal conditions of growth and under conditions of temperature and solvent stress thus implying that the Cti enzyme is post-transcriptionally regulated.
authors.affiliation: Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, 500 007, India.
authors.forename: Madanahally D
authors.initials: MD
authors.lastname: Kiran
authors.forename: Sampath
authors.initials: S
authors.lastname: Annapoorni
authors.forename: Iwane
authors.initials: I
authors.lastname: Suzuki
authors.forename: Norio
authors.initials: N
authors.lastname: Murata
authors.forename: Sisinthy
authors.initials: S
authors.lastname: Shivaji
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D017931:DNA Primers / Q000737:chemistry; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D005798:Genes, Bacterial; D017930:Genes, Reporter; D008969:Molecular Sequence Data; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic; D044224:Pseudomonas syringae / Q000201:enzymology* / Q000235:genetics*; D012313:RNA / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012997:Solvents / Q000737:chemistry; D013696:Temperature; D014158:Transcription, Genetic; D001616:beta-Galactosidase / Q000378:metabolism; D019745:cis-trans-Isomerases / Q000096:biosynthesis / Q000235:genetics*
chemical_list: D017931:DNA Primers; D012333:RNA, Messenger; D012997:Solvents; D012313:RNA; D001616:beta-Galactosidase; D019745:cis-trans-Isomerases