Studies on Monotreme Proteins. VI. Amino Acid Sequence of the ß-Chain of Haemoglobin From the Platypus, Ornithorhynchus anatinus

The amino acid sequence of the 146 residues of the p-chain of the major haemoglobin from the platypus has been determined. The soluble peptides derived from the chain by tryptic digestion were isolated by paper ionophoresis and chromatography. The amino acid sequences were determined by the dansyl-Edman procedure or by further digestion with other enzymes. The tryptic peptides were aligned by homology with other p-globins. There were 14 changes in sequence compared with echidna p-chain.</jats:p

Studies on Reduced Wool V. A Comparison of the Two Major Components

Starch-gel electrophoresis of wool proteins extracted from reduced and carboxymethylated wool gives a complex pattern in which there are two major protein bands. By a combination of chromatography on DEAE-cellulose and gelfiltration in buffers containing 8M urea these two protein components have been isolated. The amino acid composition and some properties of these two fractions are reported. A comparison of the amino acid composition and of peptide maps of tryptic digests of the two fractions shows distinct differences between them, and by labelling with 2-[14C]iodoacetate the distribution of the peptides containing S-carboxymethylcysteine residues were also shown to be different.</jats:p

Multiple Haemoglobins of the Bivalve Mollusc Anadara Trapezia

The respiratory proteins of the invertebrate marine mollusc A. trapezia have been separated by a combination of gel filtration and ion-exchange chromatography. There is a major tetrameric haemoglobin, HbI, of molecular weight approximately 67000 and two minor polymorphic haemoglobins HbIIa and HbIIb that are dimeric with molecular weight approximately 31000, in agreement with previous reports in the literature.</jats:p

Haemoglobins of the Shark, Heterodontus portusjacksoni

The haemoglobins of the Port Jackson shark, H. portusjacksoni, were resolved by cation-exchange chromatography of their carboxymethylated forms into two fractions, Hb-I and Hb-II, which were present in approximately equal proportions. A third, non-haem, acidic protein component, representing 5 % of the total protein, was also resolved. This protein is apparently of high molecular weight and is present in different polymorphic forms. The haemoglobins of the shark are subject to rapid aggregation, by disulphide bond formation, following lysis of the red cells. The aggregation is reversed by treatment with thiols, and prevented by combination of the two to four 'reactive' thiol groups with iodoacetate or other thiol-blocking reagents. The molecular weights of the haemoglobins are approximately 61 000, suggesting a tetrameric molecule.</jats:p

Myoglobin of the Shark Heterodontus Portusjacksoni: Isolation and Amino Acid Sequence

Myoglobin isolated from red muscle of the shark H. portusjacksoni was purified by ion-exchange chromatography on sulfopropyl-Sephadex and gel-filtration. Amino acid analysis and sequence determination showed 148 amino acid residues. The amino terminal residue is acetylated as shown by mass spectrographic analysis of N-terminal peptides. There is a deletion of four residues at the amino terminal end as well as one residue in the CD interhelical area relative to other myoglobins.</jats:p

Amino Acid Sequences Containing Half-Cystine Residues in Ovalbumin

Ovalbumin is known to have six half-cystine residues with four thiol groups and one disulfide bond.</jats:p

Studies on Reduced Wool. VII. The Complexity of One of the Major Components

Amajorcomponent (component 8) isolated from reduced and carboxymethylated wool has been studied chemically after digestion with trypsin and after reaction with cyanogen bromide.</jats:p

Studies on Marsupial Proteins VI. Evolutionary Changes in ?-Globins of the Macropodidae and the Amino Acid Sequence of ?-Globin From Potorous Tridactylus

Haemoglobins from 13 species of the subfamily Macropodinae and one species of the subfamily Potoroinae have been studied.</jats:p

The Amino Acid Sequence of the Large Plakalbumin Peptide and the C-Terminal Sequence of Ovalbumin

The amino acid sequence of a 33-residue peptide isolated from plakalbumin by gel filtration in 6M urea at pH 3 and derived from the C-terminal portion of ovalbumin has been determined. Enzyme digestion of the hydrophobic areas by thermolysin, papain, ana subtilisin BPN' gave peptides with overlapping sequences. The peptides were fractionated by a combination of paper ionophoresis and chromatography and their sequences determined by the dansyl-Edman technique.</jats:p

N-Acetyl Groups in Wool and Extracted Wool Proteins

N . acetyl groups have been shown to exist in wool and in proteins extracted from wool after reduction with mercaptoethanol followed by alkylation with iodoacetate or after oxidation with performic acid. The evidence suggests that these acetyl groups are located on N-terminal amino groups of peptide chains rather than on the E-amino groups of lysine.</jats:p