RT Journal Article SR Electronic(1) A1 Hunter, C. Neil A1 Coomber, Shirley A.YR 1988 T1 Cloning and Oxygen-regulated Expression of the Bacteriochlorophyll Biosynthesis Genes bch E, B, A and C of Rhodobacter sphaeroides JF Microbiology, VO 134 IS 6 SP 1491 OP 1497 DO https://doi.org/10.1099/00221287-134-6-1491 PB Microbiology Society, SN 1465-2080, AB Four mutants of the photosynthetic bacterium Rhodobacter sphaeroides were isolated which were incapable of photosynthetic growth due to inability to synthesize bacteriochlorophyll. A Rb. sphaeroides gene bank was constructed in the mobilizable vector pSUP202 and was transferred into these mutants using the helper plasmid pRK2073. Three clones that produced photosynthetic transconjugants from one or more of the bch mutants were isolated and characterized. These clones were used as probes to estimate levels of specific transcripts in cells undergoing a 100-fold increase in bacteriochlorophyll content. The maximum level of transcripts was observed at an early stage of photosynthetic membrane synthesis when only 7% of the eventual level of pigment had been synthesized., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-134-6-1491