A brain protein (P30) that inmunoreacts with a polyclonal antipancreatic carboxypeptidase A antibody shows properties that are shared with tubulin carboxypeptidase.

WEIZETFEL J.C.,; SMANIA A.M,; BARRA H.S,; ARGARAÑA C.E.

SPRINGER

Lugar: .; Año: 1997 vol. 170 p. 139 - 139

preparation of tubulin carboxypeptidase partially purified from bovine brain was found to contain a protein of molecular mass 30 kDa (P30) as determined by SDS-PAGE, that is recognized by a polyclonal anti-bovine pancreatic carboxypeptidase A. However, this protein is different from pancreatic carboxypeptidase A as judged by the isoelectric point and the pattern of peptides produced by trypsin digestion. The isoelectric point of P30 was similar to that found for tubulin carboxypeptidase (9 ± 0.2). When the tubulin carboxypeptidase preparation was subjected to gel filtration chromatography under low salt concentration, P30 behaved as a protein of molecular mass 38 kDa whereas tubulin carboxypeptidase eluted at a position of 75 kDa molecular mass. However, when the chromatography was performed at relatively high salt concentration they behaved as proteins of 49 and 56 kDa, respectively. We considered that P30 may be an inactive monomeric form of the dimeric tubulin carboxypeptidase. Ho