Subategory:

Mutants

Description:

R116-1B was recovered as a photosynthesis-competent revertant after methyl-methanesulfonate mutagenesis of rbcL-L290F mt+ (68-4PP). It results from a mutation in rbcS2 that causes an N54S substitution (AAC-AGC) in the Rubisco small subunit, which increases the CO₂/O₂ specificity of the original mutant enzyme. Gene-centromere mapping indicated that rbcS2 is 20 map units from its centromere. This strain was recovered from a cross between the original revertant R116-1B mt+ and pf2 mt-. It has been maintained with acetate medium in darkness to prevent selection for secondary mutations that may improve Rubisco function.

Species:

Chlamydomonas

Locus:

rbcL, RBCS2, PF2

Chromosome:

Chloroplast,2,11