CC-4819 rbcL-T173I mt+ (69-12Q) (original isolate)
$30.00
From Robert J. Spreitzer, University of Nebraska, July 2014
Phenotype: requires acetate, sensitive to light
The 69-12Q chloroplast mutant was recovered by screening a collection of acetate-requiring mutants for lack of complementation with a known Rubisco rbcL mutant. It results from a T173I substitution (ACA-ATA) in the chloroplast-encoded large subunit of Rubisco, which eliminates carboxylase activity but not Rubisco holoenzyme assembly (Spreitzer et al. 1988). This active-site residue is normally Ile in Rhodospirillum rubrum Rubisco, and replacing that residue with Thr also causes a decrease in carboxylase activity (Chene et al. 1997). Selection for photosynthesis-competent revertants of rbcL-T173I yielded only true revertants (Spreitzer 1998). This strain has been maintained with acetate medium in darkness since its isolation.
Chene P, Day AG, Fersht AR (1997) Role of isoleucine-164 at the active site of Rubisco from Rhodospirillum rubrum. Biochem Biophys Res Com 232:482-486
Spreitzer RJ (1998) In JD Rochaix, M Goldschmidt-Clermont, S Merchant, eds, The Molecular Biology of Chloroplasts and Mitochondria in Chlamydomonas, Kluwer Academic Publishers, Dordrecht, pp 515-527
Spreitzer RJ, Brown T, Chen Z, Zhang D, Al-Abed SR (1988) Missense mutation in the Chlamydomonas chloroplast gene that encodes the Rubisco large subunit. Plant Physiol 86:987-989