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W Arber

Publications and source records attributed to W Arber.

At least 91 records · Page 5Linked to original sources
PubMed1979

Multiple physical differences in the genome structure of functionally related bacteriophages P1 and P7.

Comparative restriction cleavage analysis of the genomes of bacteriophage P7, of several recombinant phages between P7 and P1, and of bacteriophage P1 allowed to draw PstI, Bg/II, BamHI and HindIII cleavage maps of all genomes studied. The data obtained complement Yun and Vapnek's (1977) conclusions with regard to areas of major nonhomology based on electron microscopical heteroduplex analysis and they identify several additional minor differences between P1 and P7. The use of hybrid phage strains allowed to locate the genes for particular functions on the physical genome map.

Chromosome Mapping↗
PubMed1978

E. coli K-12 pel mutants, which block phage lambda DNA injection, coincide with ptsM, which determines a component of a sugar transport system.

Escherichia coli pel- mutants inhibit the penetration of bacteriophage lambda DNA into the cell. Using P1 mediated cotransduction, we mapped pel- mutations between markers fadD and eda in the interval of minute 40 of the revised E. coli K-12 map. This places pel in the same region as genes kdgR and ptsM. Mutations in kdgR usually do not alter the Pel phenotype, and vice versa. In contrast, about 30% of ptsM- mutants are also pel-, and all pel- mutants isolated are ptsM-. These results suggest that pel and ptsM are one and the same gene. This interpretation would identify the bacterial product required for injection of phage lambda DNA as a component of the phosphoenolpyruvate-dependent phosphotransferase system specific for mannose, glucosamine, glucose and fructose. However, the experimental results do not exclude an alternative explanation: that pel and ptsM identify two closely linked genes which would be simultaneously affected at high frequency by a particular mutational event.

Biological Transport↗
PubMed1977

Physical mapping of BglII, BamHI, EcoRI, HindIII and PstI restriction fragments of bacteriophage P1 DNA.

A cleavage map of bacteriophage P1 DNA was established by reciprocal double digestion with various restriction endonucleases. The enzymes used and, in parenthesis, the number of their cleavage sites on the P1clts genome are: PstI (1), HindIII(3), BglII (11), BamHI (14) and EcoRI (26). The relative order of the PstI, HindIII and BglII sites, as well as the order of 13 out of the 14 BamHI sites and of 17 out of the 26 EcoRI sites was determined. The P1 genome was divided into 100 map units and the PstI site was arbitrarily chosen as reference point at map unit 20. DNA packaging into phage heads starts preferentially at map unit 92 and it proceeds towards higher map units. The two inverted repeat sequences of P1 DNA map about at units 30 and 34.

Base Sequence↗