Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Monoclonal antibodies have been generated to a chimeric peptide comprised of Escherichia coli beta-galactosidase fused to the amino acid sequence 69-207 of human preproenkephalin A. Two monoclonal antibodies, PE-1 and PE-2, were identified by their ability to recognize the same segment of proenkephalin A fused to the cII gene product of the E. coli bacteriophage lambda. The binding domains of PE-1 and PE-2 have been broadly located, with respect to the primary translation product, within the amino acid sequences 152-207 and 84-131, respectively. Immunoblot analysis of total bovine adrenomedullary chromaffin granule lysate reveals PE-1 and PE-2 immunoreactive forms of observed molecular mass 35, 33, 29, 24, 22, and 15 kDa, and an 18-kDa PE-1 immunoreactive form. Separation of granule membranes from their contents reveals differential membrane association of these high molecular weight polypeptides. There is preliminary evidence that PE-1 may be detecting a subset of polypeptides where shortening from the NH2 terminus has occurred. We postulate that the 35-kDa form represents the intact bovine enkephalin precursor of predicted molecular mass 27.3 kDa. This experimental approach should be generally applicable to the generation of antibodies which will recognize intact peptide precursors together with their post-translational cleavage products.
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PMID:Monoclonal antibodies to a proenkephalin A fusion peptide synthesized in Escherichia coli recognize novel proenkephalin A precursor forms. 246 43

Two mouse monoclonal antibodies (PE-1 and PE-2) raised to a beta-galactosidase-preproenkephalin A(69-207) fusion peptide recognize pro-enkephalin A (pro-enk-A) peptides of 33-5 kDa isolated from bovine adrenal chromaffin granules. The preliminary characterization of the high molecular weight adrenomedullary pro-enk-A peptides recognized by PE-1 and PE-2 is described. The high molecular weight peptides were resolved after Sephadex G-50 chromatography and high-performance liquid chromatography (HPLC) into three components (peaks I, II and III). Immunoblot analysis showed each HPLC peak to be heterogeneous. Peak I contained PE-1-and PE-2-immunoreactive peptides of 33, 29, 24 and 22 kDa; peak II contained a peptide of 22 kDa recognized by PE-2, and peptides of 24 and 22 kDa recognized by PE-1; peak III contained a PE-2-immunoreactive peptide of 15 kDa and PE-1-immunoreactive peptide of 18 kDa. Using polyclonal antibodies to peptide F and methionineenkephalin-Arg6-Gly7-Leu8 (MetEnk-RGL), the 22 kDa band cross-reacted with both MetEnk-RGL and peptide F antibodies, whilst the 24 kDa band was shown to possess predominantly MetEnk-RGL immunoreactivity. The 15 kDa (PE-2-immunoreactive) band was recognized by the peptide F but not the MetEnk-RGL antibody, whereas the polyclonal antibodies did not recognize the 18 kDa (PE-1-immunoreactive) band. We propose that the immunological and size characteristics of some of these peptides (29, 24/22, 15 kDa) suggest their similarity to the peptides of predicted molecular mass 23.3, 18.2 and 12.6 kDa previously found in bovine adrenal medulla. The results also indicate the existence of high molecular weight pro-enk-A peptides shortened at the N-terminus. The use of an immunoradiometric assay designed to measure the proenk-A-derived 18.2 kDa peptide using PE-2 and an affinity purified and radioiodinated MetEnk-RGL IgG has supported these findings.
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PMID:Identification of high molecular weight peptides in bovine adrenomedullary chromaffin granules using monoclonal antibodies to a preproenkephalin A fusion peptide. 277 54