Amino acid-activating systems from pig liver

The interaction of ‘soluble’ ribonucleic acid, magnesium ions and sulphydryl groups in the control of amino acid-dependent pyrophosphate-exchange reactions

“…Conceivably, the effects may be correlated with their response to Mg2+ ions and to 'soluble' RNA. Allen et al (1960b) suggested that sulphydryl groups might participate in the reaction mechanisms of amino acid activation. Perhaps the transfer of the activated amino acid to the adenosyl 338 1961 unit involves a chelate mechanism and a thio ester intermediate (Hele, 1960a), along the lines suggested by Ingraham & Green (1958) for the activation of acetate. SUMMARY 1.…”

“…These amino acid-activating enzymes, like the acetateactivating enzyme of ox-heart mitochondria (Hele, 1954), can be further purified by gels in the presence of (NH4)2SO4.…”

The extraction and assay of aminoacyl-transfer-ribonucleic acid synthetases of tobacco leaf

“…The incorporation of [32P]pyrophosphate into ATP was measured by the method of Hele & Finch (1960) with micro-filter tubes supplied by A. Gallenkamp Ltd. (no.…”

Amino Acid Selection in Protein Biosynthesis

“…Aminoacyl-s-RNA synthetases have been isolated from rat liver (Hele, 1961 ;Glenn, 1961;Fraser, 1963;Fraser & Klass, 1963;Boyko & Fraser, 1964), pig liver (Hele & Finch, 1960;Webster, 1961 b), guinea-pig liver (Ogata et al 1961) and from hog pancreas (Schweet, 1957). These enzymes have also been reported from chick embryo (Coronado, Mardones & Allende, 1963 ;Bublitz, 1966), from rat mammary gland (Bucovaz & Davis, 1961), from mouse and human skeletal muscle (Pennington, 1960), from frog and tadpole liver (DeGroot & Cohen, 1962), from pig thyroid (Alexander, 1963), from the small intestinal epithelium of hamsters, rats and guinea-pigs (Kessler, Eisler & Janowitz, 1965) and from four classes of Chordata (Glebov, Zaitseva & Belozerskii, 1965).…”