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G N Godson

Publications and source records attributed to G N Godson.

At least 73 records · Page 4Linked to original sources
PubMed1978

Nucleotide sequence of bacteriophage G4 DNA.

The 5,577 nucleotide long sequence of bacteriophage G4 DNA has been determined using the 'plus and minus' and chain termination methods of DNA sequencing. This sequence has been compared with that of the closely related bacteriophage phiX174 (refs 1, 55). In the coding regions there is an average of 33.1% nucleotide sequence differences between the two genomes, but the distribution of these changes is not random and the sequence of some genes is more conserved than others. There is less sequence similarity between the untranslated intergenic regions of G4 and phiX174, but despite this the sequences of the J/F, F/G and H/A untranslated spaces in both genomes have similar sized hairpin loops, which may be related to their function.

Bacteriophages↗
PubMed1978

Nucleotide sequence of the J gene and surrounding untranslated regions of phage G4 DNA: comparison with phage phiX174.

A 290 nucleotide long region of the bacteriophage G4 genome including the end of the overlapping genes D and E, the entire gene J and the untranslated region between genes J and F has been sequenced and compared with the same region in bacteriophage phiX174. Deletions, insertions, duplications and single base changes in G4 relative to phiX174 have resulted in the following changes: the loss of the phiX174 overlapping gene Dtermination and gene J initiation codons, resulting in their separation by 32 untranslated nucleotides; the deletion of one third of the gene J coding region, so that the G4 protein is only 24 amino acids long compared with 37 amino acids in phiX174; and the establishment of a long untranslated region between G4 genes J and F, which despite many nucleotide changes retains the ability to form a stable hairpin loop in the same place and with the same geometry as in phiX174. The G4 overlapping gene E is longer than in phiX174 and extends beyond gene D. Sixteen nucleotides at the end of genes D and E in phiX174 are duplicated in G4 before gene J.

Base Sequence↗
PubMed1978

Nucleotide sequences of the separate origins of synthesis of bacteriophage G4 viral and complementary DNA strands.

Bacteriophage G4 has physically separated origins of synthesis of its viral and complementary DNA strands. Chain termination and "plus and minus" DNA sequencing methods have been used to obtain the nucleotide sequence of these two origins. The unique origin at which the complementary DNA strand is initiated has located in the untranslated region between genes F and G. This sequence, which has considerable secondary structure, contains a stretch which is complementary to the RNA primer that is observed during synthesis in vitro of the G4 complementary DNA strand [Bouché, J.P., Rowen, L. & Kornberg, A. (1978) J. Biol. Chem., in press]. This G4 origin shows extensive sequence homology with the bacteriophage lambda origin of DNA replication [Denniston-Thompson, K., Moore, D. D., Kruger, D. E., Furth, M. E. & Blattner, F. R. (1977) Science 198, 1051-1056]. The sequence around the site in gene A at which G4 viral DNA strand synthesis is initiated by the nicking action of the cistron A protein is very similar to that of bacteriophage phiX174. An (A + T)-rich stretch flanked by (G + C)-rich sequences may be involved in the interaction between the DNA and protein.

Bacteriophages↗
PubMed1976

Specific inhibition of phospholipid synthesis in plsA mutants of Escherichia coli.

plsA mutants of Escherichia coli are temperature-sensitive strains which possess two enzymes of abnormal thermolability, sn-glycerol 3-phosphate acyltransferase and adenylate kinase. Phospholipid synthesis is inhibited after shift of plsA mutants to temperatures at the lower end of the nonpermissive temperature range. This inhibition is not due to inactivation of the adenylate kinase activity since nucleic acid (and hence adenosine 5'-triphosphate) synthesis is inhibited only slightly. These results show that in vivo inactivation of the sn-glycerol 3-phosphate acyltransferase can be observed under conditions which allow normal adenylate kinase function.

Acyltransferases↗
PubMed1975

Specificity of the S1 nuclease from Aspergillus oryzae.

Conditions are described for digesting single-stranded DNA by S1 nuclease without introducing breaks in double-stranded DNA. The enzyme is inhibited by low concentrations of various compounds of phosphate. Under certain conditions S1 nuclease cleaves the strand opposite a nick in bacteriophage T5 DNA; under other conditions, the enzyme cleaves a loop in one strand of heteroduplex lambdaDNA while leaving the opposite strand intact. S1 nuclease makes many single strand breaks in ultraviolet-irradiated duplex lambdaDNA. Superhelical DNA of phiX174 (Form I) is converted first to a relaxed circular molecule (Form II), and then to a linear molecule (Form III) by cleavage at one site per molecule. Since the cleavage occurs at many sites in the population of molecules, the partially single-stranded regions in phiX174 superhelical DNA are not determined by specific nucleotide sequences.

Adenine Nucleotides↗