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H D Niall

Publications and source records attributed to H D Niall.

At least 73 records · Page 4Linked to original sources
PubMed1971

Calcitonin.

Explore the source record for details and available documents.

Amino Acid Sequence↗
PubMed1971

Synthesis of a biologically active N-terminal tetratriacontapeptide of parathyroid hormone.

Determination of the amino acid sequence of bovine parathyroid hormone has led to the synthesis of a tetratriacontapeptide corresponding to the amino-terminal 1-34 residues of the native molecule. The specific biological effects of this synthetic peptide on bone and kidney are qualitatively identical to those of the native hormone in classical bioassays in vivo and in several systems in vitro. Potency of the synthetic peptide equals or exceeds that of a biologically active fragment of comparable size isolated from the native hormone; the synthetic and natural peptides show complete immunological cross-reactivity. Thus, essential requirements for the physiological actions of the peptide on both skeletal and renal tissue are contained within the 34 amino-terminal amino acids. The potency of the synthetic peptide, relative to that of the native (84-amino acid) polypeptide, is greater in vitro than in vivo; this suggests that the carboxyl terminal two-thirds of the native hormone may protect the circulating polypeptide from rapid metabolic degradation.

Adenylyl Cyclases↗
PubMed1971

Sequences of pituitary and placental lactogenic and growth hormones: evolution from a primordial peptide by gene reduplication.

Human placental lactogen has been found to resemble human pituitary growth hormone very closely in amino acid sequence, about 80% of the residues examined being identical in the two molecules when a revised sequence for growth hormone is used as the basis for comparison. The structural features responsible for the differing biological potency of the two hormones may therefore reside in rather limited regions of primary structure. The observation of internal sequence homologies within the pituitary growth hormone and prolactin and the placental lactogen molecules suggests that these polypeptide hormones may have evolved by genetic reduplication from a smaller common ancestral peptide. This finding directs further attention to subfragments of these molecules as possible possessors of intrinsic somatotrophic and lactogenic activity.

Amino Acid Sequence↗
PubMed1970

The N-terminal amino acid sequence of two avian leukosis group specific antigens.

Two group-specific antigenic proteins from an avian leukosis virus have been compared by amino acid analysis, tryptic peptide fingerprinting, and N-terminal sequence determination, and found to be dissimilar. There was microheterogeneity in the structure of the protein gs-b at residues 6; threonine and glutamic acid were found.

Amino Acid Sequence↗
PubMed1969

Amino acid sequence of salmon ultimobranchial calcitonin.

Salmon ultimobranchial calcitonin has been isolated and rendered pure, as demonstrated by several chemical criteria. Its amino acid sequence was determined by means of manual Edman degradation of the intact molecule and of several peptide subfragments. Results of automated degradation provided confirmation of the structure. The salmon molecule possesses, in common with other calcitonins, a 32-amino acid peptide chain terminating in prolinamide and containing half-cystine residues at positions 1 and 7. Although the sequence of the salmon hormone differs considerably from that of the porcine, bovine and human calcitonins, the four hormones are homologous in 9 of 32 positions. The much higher biological potency possessed by the salmon calcitonin makes it of particular interest for future structure function studies.

Amino Acid Sequence↗