Structural organization of the S. oneidensis MR-1 so2426 locus. (A) Schematic representation of the so2426 gene region. ORFs located upstream and downstream of so2426 (black arrow) are indicated by open arrows, which also indicate the direction of transcription. The deduced proteins of the ORFs flanking so2426 have the following annotations based on the J. Craig Venter Institute's Comprehensive Microbial Resource http://cmr.tigr.org webcite: SO2421 is a L-asparaginase I; SO2422 is a conserved hypothetical protein; SO2423 is a hypothetical protein; SO2424 is a zinc carboxypeptidase domain protein; SO2425 is a hypothetical protein; SO2426 is a DNA-binding response regulator; SO2427 is a putative TonB-dependent receptor; and SO2428 is a hypothetical protein. The locations of the oligonucleotide primers (P1–P9) used for RT-PCR are shown by the small solid arrows. The expected PCR product sizes for the different primer pairs are given below. (B) Agarose gel (1%) electrophoresis of amplified DNA fragments derived from S. oneidensis MR-1 cDNA templates under conditions of chromate stress or no stress. Lane designations: (1) 100-bp DNA ladder; (2) PCR primer pair P1/P4, (3) P1/P5, (4) P1/P6, (5) P1/P7, (6) P2/P8, (7) P9/P3, (8) blank, (9) 100-bp DNA ladder, (10) P1/P4, (11) P1/P5, (12) P1/P6, (13) P1/P7, (14) P2/P8, (15) P9/P3, (16) chromate-treated total RNA used as the template in PCR amplification with P1/P4 (negative control), and (17) non-stressed total RNA used as the template in PCR amplification with P1/P4 (negative control).
Chourey et al. BMC Genomics 2008 9:395 doi:10.1186/1471-2164-9-395