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Biomedical subjects

A Patthy

Publications and source records attributed to A Patthy.

52 records · Page 3Linked to original sources
PubMed1977

Preparation and characterization of Ng-mono-, di- and trimethylated arginines.

A simple procedure is described for the synthesis of N-guanidino methylated ariginines. The yields of all methylarginines exceed those obtained by earlier procedures. Trimethylarginine - an amino acid not found in natural sources - has also been synthesized with this technique. Studies with arginine specific dicarbonyl reagents showed that methylation of guanidino-groups decreases the reactivity of methyl-arginines, only monomethylarginine reacting at a rate comparable to that of arginine.

Arginine↗
PubMed1976

Action of thrombin on ovine, bovine and human pituitary growth hormones.

1. This communication reports the action of bovine thrombin on ovine, bovine and human growth hormones. Thrombin cleavage was shown to be restricted to a single homologous peptide bond in all three growth hormones (at sequence positions 133--134 of the ovine and bovine hormones). 2. Ovine growth hormone was the most sensitive to the action of thrombin, bovine growth hormone was attacked to a relatively less extent, and human growth hormone was the most resistant to the enzyme. 3. After reduction and carbamidomethylation of the disulfide bonds in thrombin modified ovine growth hormone, the two fragments (residues 1--133 and 134--191) were isolated. The large NH2-terminal thrombin fragment of the hormone (residues 1--133) was found to be inactive in the rat tibia test, whereas a tryptic fragment (residues 96--133) isolated in an independent way gave measurable responses.

Amino Acid Sequence↗
PubMed1975

Specific colour reaction for the determination of lysine and/or ornithine.

A simple procedure was worked out for the direct spectrophotometric determination of lysine and/or ornithine in hydrolysates of proteins and protein-containing materials. The method is based on the estimation of the coloured compound formed in the reaction of lysine and ornithine with furfurol. Since the reaction is specific for lysine and ornithine and separation of amino acids is not necessary for their determination the method is suitable for large scale screening of protein samples. The lower limit of detection is 0.5 mug for lysine and 2 mug for ornithine and the accuracy of the method is +/- 0.5% and +/- 2% respectively.

Lysine↗