Eight mutant strains of which are capable of growing on succinate but not on methanol are described. Three of these contain single enzyme deficiencies while five have pleiotropic deficiencies. Some of the mutant strains are revertible to the wild-type phenotype by -methyl--nitro--nitrosoguanidine and ethyl methanesulphonate and others are not.

Crosses between strains were performed by transformation using DNA prepared from cells which were streptomycin-resistant and either methanol or methanol. The frequencies of streptomycin-resistant transformants and methanol transformants were determined independently. Four of the methanol mutant strains appeared to contain mutations which are linked to each other (group 1) while the other four (group 2) appeared to contain mutations not linked to the first four. In reciprocal crosses with the group 2 markers, two appeared to be linked to each other, while the other two were not linked to any mutant tested.

The data presented were used to construct a model for the organization of these genes in which the CO-binding cytochrome is not linked to the five genes for C-specific enzymes. In this model, the expression of six C-specific functions is controlled by a common regulatory agent.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error