Bacteriophage soluble

T2r bacteriophage. The molar proportions of the bases in the acid-soluble fraction of normal Escherichia coli strain B, relative to adenine, were as follows adenine, 1.0 guanine, 0.99 cytosine, 0.09 uracil, 0.95 and thymine, 0.09. The figures for the infected system are in sharp contrast to those of the normal system adenine, 1.0 guanine, 0.11 cytosine, 0.08 lu-acil, 0.38 and thymine, 0.54. 

Other notable free protein structures include the following. Uniquely, Hung and co-workers have determined the high-resolution structure of Mu B, a protein required for the strand transfer step of bacteriophage Mu DNA transposition, at extreme salt concentrations i.e. 1.5 M NaCl. Their approach for structural determination in high salt may be generally applicable for proteins that do not crystallize or those that are plagued by solubility problems... 

We selected scFvs from a combinatorial phage display library using both phosphorylated and nonphosphorylated forms of a C-terminal y-H2AX peptide. Figure 2B shows die peptide sequence used for selection. Ten separate bacteriophage isolates were chosen for further characterization. Soluble scFvs were produced in the periplasm of an E. coli host. Periplasmic extracts were either used direcdy or as a source of material for further purification. 

The RNA replication complex of a picornavims is bound to smooth cytoplasmic membranes (10, 16). In order to obtain a soluble RNA dependent activity it is necessary to dissociate the enzyme from the membranes by means which adversely affect the activity of the enzyme. It is also more laborious and costly to grow and infect large quantities of animal cells than to carry out a large scale infection of E. coli with an RNA bacteriophage. So far, because of these limitations, the isolation of a picornavims replicase was carried out with very dilute solutions of enzyme-protein, a... 

Beyond the well-known base eomponents, several other bases and nucleosides occurring only in special nucleic acids have reeently been discovered. Some bacterial viruses (bacteriophages) contain in their nucleie acids the bases 6-hydroxymethylcytosine and S-hydroxymethyluracil. Soluble ribonucleic acid (i.e., transfer ribonucleic acid, see Section 6) contains pseudowridine, a 5-ribo-syluracil in which the sugar and the pyrimidine moieties are linked through a C—C bond. Transfer ribonucleie acid also contains a small proportion of methyl derivatives of the main nucleosides (especially N-methyl derivatives). 

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