Two arginyl-transfer ribonucleic acid (tRNA) synthetase (EC 6.1.1.13, arginine: ribonucleic acid ligase adenosine monophosphate) activities were found in extracts of Escherichia coli strains AB1132 and NP2. The two arginyl-tRNA synthetase activities in extracts of strain AB1132 were found to be separable by diethylaminoethyl-cellulose column chromatography, Sephadex column fractionation, and by...

Initial extracts from etiolated plants contained two aggregates of phytochrome. A major fraction was almost excluded by Sephadex G-200 and was within the fractionation range of Sepharose 4 B. A minor fraction was within the fractionation range of Sephadex G-200. Modifications of a previous isolation procedure which allowed retention of this aggregation state are reported. With respect to gel fi...

Two nonmitochondrial forms of DNA polymerase are demonstrated in regenerating rat liver and Morris hepatomas 7777, 7800, and 7794A. The enzymes have been partially purified from subcellular fractions of these tissues. The purification procedure involves fractionation with ammonium sulfate and chromatography on diethylaminoethyl cellulose and on phosphocellulose. The enzymes have different physi...

1. The isolation of human plasma prekallikrein was achieved by fractionating human plasma on diethylaminoethyl cellulose (DEAE) in the presence of heparin.2. Heparin was shown to inhibit the activation of prekallikrein during the isolation procedure.3. The isolated prekallikrein fraction had some kallikrein activity which could be inhibited by diisopropylfluorophosphate (DFP) without affecting ...

Six polysaccharide preparations, lentinan, LC-11, LC-12, LC-13, EC-11, and EC-14, were isolated from the watersoluble extracts of Lentinus edodes (Berk.) Sing., an edible mushroom, by fractional precipitation with ethanol and cetyltrimethylammonium hydroxide, fractional solubilization with acetic acid, and diethylaminoethyl cellulose column chromatography. The first two polysaccharide preparati...

By using a strain of Salmonella typhimurium, we detected the presence of an enterotoxin, as determined by the rabbit ileal loop assay, in various complex and defined media. The enterotoxin was concentrated by ultrafiltration of culture supernatant fluids and eluted in and adjacent to the void volume of a Sephadex G-100 column. This suggested that the enterotoxic factor was of a relatively high ...

Increases in deoxyribonuclease activity assayed at alkaline pH can be observed in poxvirus-infected cells when native or denatured deoxyribonucleic acid (DNA) is used as substrate. The deoxyribonuclease assayable with native DNA as substrate, induced in HeLa cells by cowpoxvirus or vaccinia virus WR, can be separated from the corresponding enzyme present in normal cells by chromatography on die...

A protein was isolated from bovine thymus that was shown to accelerate the appearance of hemolysin to sheep erythrocytes in neonatal mice. The isolation procedure consisted of saline homogenization, ammonium sulfate precipitation, and methanol precipitation, followed by chromatography on diethylaminoethyl-cellulose and two chromatographies on Sephadex G-150. The protein was shown to be homogene...

its purification a benzoylated diethylaminoethyl cellulose column (7), after which we passed the preacylated tRNAsi^c: over an RPC-II column. This last column is described in Chart 1. The Chromatographie profile of the phenylalanine acceptor activity presented 3 distinct peaks. Those indicated as Phe 1 and Phe 2 were also normally present in tRNAs^a 0); Phe X is a new tRNA that we first observe...

The deoxyribonucleic acid (DNA) of competent wild-type Haemophilus influenzae and rec1 mutant cells contains single-strand regions, as judged by alkaline sucrose sedimentation, benzoylated naphthoylated diethylaminoethyl-cellulose fractionation, and digestion with an enzyme specific for single-strand regions in DNA. In contrast, the DNA of competent rec2 cells does not contain single-strand reg...