T4 phage

Myoglobin, hemoglobin Thermolysin domain 2 T4 phage lysozyme domain 2 Papain domain 1... 

Tyrosyl-tRNA synthetase dl, d2 Thermolysin dl, d2 T4 phage lysozyme dl, d2 Glucosephosphate isomerase dl, d2 Pyruvate kinase dl, d2 Pyruvate kinase d2, d3 Lactate dehydrogenase dl, d2 Alcohol dehydrogenase dl, d2 Glyceraldehyde-phosphate dehydrogenase dl,d2... 

Figure 5.17 The assembly of a T4 phage from its constituents. The numbers next to the arrows refer to gene products that are required for a particular step in assembly. (Adapted from Wood, 1973.)...

Allen, J.R. Lasser, G.W. Goldman, D.A. Booth, J.W. Mathews, C.K. T4 phage deoxyribonucleotide-synthesizing enzyme complex. Further studies on enzyme composition and regulation. J. Biol. Chem., 258, 5746-5753 (1983)... 

The T4 phage tail is assembled in a separate sequence. Six copies of each of three different proteins form a "hub" with hexagonal symmetry (Fig. 7-29). 

Anti-Hammond effect 591 Antimutator strain of T4 phage 390,... 

A new RNase activity, tentatively named RNase V, was found in cell-free extracts of E. coli. Ribonuclease V is an exoribonuclease attacking mRNA from 5 to 3 terminal producing 5 -mononucleotides. It is characterized by the requirements of ribosomes, G and T factors, tRNA, K+ or NH4+, Mg2+, GTP and a sulfhydryl compound by its specificity and by the fact that it degrades poly U, poly A, T4 phage mRNA or E. coli mRNA, but not ribosomal RNA (132). 

Sadowski and Hurwitz have described two endonucleases synthesized in T4 phage-infected E. coli which they have named T4 endonucleases II and IV (66). 

Glucosylated oligonucleotides obtained from T4 phage DNA by acid DNase digestion are resistant to spleen exonuclease (28). It has been reported that acetylation of the 2 -OH groups of tRNA completely inhibits the action of the enzyme, whereas venom exonuclease is not affected (29). The naturally occurring methylation of sugars and bases in tRNA does not seem to hinder the action of spleen exonuclease. 

DNA strand. At the expense of one molecule of ATP, two DNA strands are joined via a phosphodi-ester bond. Although eukaryotic and T4 phage DNA ligase use ATP as the adenyl group donor in this reaction, E. coli DNA ligase utilizes NAD+ (Fig. V-16). 

Fig. 3.3. Folding transition of T4 phage DNA induced by the addition of the triva-lent cation spermidine. The abscissa and ordinate axes are the spermidine concentration and long axis length of DNA measured by fluorescence microscopic observation (see [11] for more details)...

Matthews, B. W. (1975). Comparison of the predicted and observed secondary structure of T4 phage lysozyme. Biochim Biophys Acta 405,442-51. 

Display on T4 phage has been reported on a minor coat protein called fibritin [29] and on two outer capsid proteins, HOC and SOC [30, 31]. HOC and SOC accept, respectively, N-terminal and C-terminal fusions. High levels of full-length protein display have been obtained with both proteins between 10 and 40 copies of a protein of 183 amino acid residues were expressed per phage particle [32]. 

Lariviere L, Morera S. A base-flipping mechanism for the T4 phage 3-glucosyltransferase and identification of a transition-state analog. J. Mol. Biol. 2002 324 483-490. 

Triple entendre. The RNA transcript of a region of T4 phage DNA contains the sequence 5 -AAAUGAGGA-3. This sequence encodes three different polypeptides. What are they ... 

We now turn from DNA replication to DNA mutations and repair. Several types of mutations are known (1) the substitution of one base pair for another, (2) the deletion of one or more base pairs, and (3) the insertion of one or more base pairs. The spontaneous mutation rate of T4 phage is about 10 per base per replication. E. coli aaA Drosophila melanogaster have much lower mutation rates, of the order of lO" . 

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