Amino acid sequences of α‐allophycocyanin B from Synechococcus 6301 and Mastigocladus laminosus

[摘要]

The primary structure of α-allophycocyanin B (α^APB) of Synechococcus 6301 was elucidated. Of the 162 amino acid residues in this polypeptide, 153 were placed by direct sequence determination and the nature of the remaining 9 residues deduced from the amino acid analysis of a peptide generated by the cleavage of α^APB with BNPS-skatole. The probable positions of these 9 residues were assigned by homology to other phycobiliproteins. α^APB showed the highest homology, 51%, to α^AP. Sequence comparisons suggest that tryptophan residues at positions 60 and 90 in α^APB might contribute to the red-shifted absorption and fluorescence emission maxima of α^APB relative to those of α^AP. N-terminal sequences of Mastigocladus laminosus α^APB, and Synechococcus 6301 α^AP and β^AP were also determined. The N-terminal 55 residues of Synechococcus 6301 β^AP isolated from the two complexes (α^APBβ^AP)₃ and (α^APβ^AP)₃, respectively, were found to be identical.

[学科分类] 生物化学/生物物理

[关键词] α-Allophycocyanin B;Phycobiliprotein;Amino acid sequence;(Synechococcus 6301;Mastigocladus laminosus);BNPS-skatole;2-(2-nitrophenylsulfenyl)-3-methylbromoindolenine;phycobiliprotein subunits and linker polypeptides of phycobilisomes are abbreviated as described by Glazer [(1985) Annu. Rev. Biophys. Biophys. Chem. 14;47-77];AP;allophycocyanin