Human free secretory component is composed of the first 585 amino acid residues of the polymeric immunoglobulin receptor.
The main objective of this work was to unequivocally determine the C-terminal sequence of human milk free secretory component (SC). It was found to end at arginine-585, i.e. 33 amino acids downstream from the major heterogeneous C-terminal residue previously identified for colostrum SC. In contrast, our data showed that the C-terminal end of SC was found to be homogeneous. Conflicting assignments, Asp/Gln, a missing Asn-211, Asp/Asn, Glu/Gln were corrected and found to agree with the cDNA sequence. An Ala/Val substitution at position 562 (domain VI) was identified. Its genetic significance is uncertain at present.
Hughes
G J
GJ
Dept. of Medical Biochemistry, Faculty of Medicine, University of Geneva, Medical Center, Switzerland.
Frutiger
S
S
Savoy
L A
LA
Reason
A J
AJ
Morris
H R
HR
Jaton
J C
JC
D000595:Amino Acid Sequence; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D008969:Molecular Sequence Data; D019056:Receptors, Polymeric Immunoglobulin / Q000737:chemistry*; D012635:Secretory Component / Q000737:chemistry*; D014357:Trypsin / Q000378:metabolism
D019056:Receptors, Polymeric Immunoglobulin; D012635:Secretory Component; D014357:Trypsin