SUMMARY: An strain unable to use gluconate was isolated by spontaneous curing of λ Δ() lysogens. Two lesions, linked to and markers, respectively, were necessary to produce this phenotype. The -linked mutation , of regulatory type, seems to affect the expression of the major system of gluconate utilization (min 75) as well as that of 6-phosphogluconate dehydratase (gene , min 41), the first enzyme of the Entner-Doudoroff pathway. A closely linked suppressor of causes constitutivity of these activities; this suppressor resembles , which is also in the region. Hence, it is possible that is a super-repressing allele of , rather than a positive controlling element. Lesion alone does not prevent the utilization of gluconate; for this, the mutation at 96.9 min is also necessary. This mutation abolishes the thermosensitive gluconokinase activity and thus eliminates the subsidiary ability to catabolize gluconate. Accordingly, seems to be allelic with , the locus postulated as being in the region specifying the thermosensitive gluconokinase.


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