Welcome! Click here to login or here to register.
 |
|||||||||||||||||||
|
|||||||||||||||||||
 |
|||||||||||||||||||
"Structure and expression of the dnaQ mutator and the RNase H genes of Escherichia coli: overlap of the promoter regions." |
Maki H, Horiuchi T, Sekiguchi M |
Published Dec. 1, 1983 in Proc Natl Acad Sci U S A volume 80 .
Pubmed ID: 6316347
Abstract:
| A 1.6-kilobase-pair DNA fragment derived from the Escherichia coli chromosome was analyzed by Tn3 transposon insertion and deletion mapping to locate a mutator gene, dnaQ (mutD), and the rnh gene that codes for RNase H. When a strong promoter, PL of lambda phage, was placed at the right- and left-side of the cloned DNA fragment, the dnaQ protein and RNase H, respectively were overproduced. These results suggested that the two genes are transcribed in opposite directions and that their promoters are located in a narrow region between the genes. Nucleotide sequence analysis confirmed this and further revealed that transcriptional and translational initiation signals for the two genes overlap. From the sequence data it was deduced that the dnaQ protein and RNase H consist of 243 and 155 triplets and have molecular weights of 27,500 and 17,500, respectively. dnaQ81 amber mutant showed two codon alterations, CAG(glutamine-195) leads to TAG(amber) and ACA(threonine-193) leads to ATA(isoleucine). The dnaQ-lacZ and the rnh-lacZ fused genes were constructed and hybrid proteins with beta-galactosidase activity were produced. From beta-galactosidase levels it was estimated that the promoter for dnaQ is 5 times more active than that for rnh. |
This publication refers to following REPAIRtoire entries:
| Proteins |
Last modification of this entry: Oct. 6, 2010
Add your own comment!
There is no comment yet.
|
|
|
|