title: Nerve growth factor from mouse submaxillary gland: amino acid sequence.
abstract: The complete amino-acid sequence of the 2.5S nerve growth factor from male-mouse submaxillary glands has been determined. The unambiguous alignment of peptides derived from tryptic, chymotryptic, thermolytic, and peptic digestion of S-carboxymethyl-, S-aminoethyl-, and native growth factor indicates that the primary subunit is composed of 118 amino acids, with amino-terminal serine and carboxyl-terminal arginine. The molecular weight of this subunit, calculated from the primary sequence, is 13,259. Thus, the native protein, which is composed of two of the subunits, has a molecular weight of 26,518. These values, as well as the final amino-acid composition, are in excellent agreement with those determined by direct measurement with undigested growth factor. The alignment of the three disulfide bonds, determined from a combination of peptic and thermolytic digestions, is I-IV, II-V, and III-VI. The latter two pairs are located in a closed loop of 14 amino acids, by virtue of the fact that half-cystinyl residues V and VI are separated by only a single residue in the linear sequence. Assignment of the side-chain amides showed that 7 of 11 aspartic acid residues and 2 of 8 glutamic acid residues are present as amides. This distribution of charged residues is entirely consistent with the observed isoelectric point of 9.3.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001322:Autoanalysis; D002845:Chromatography; D002918:Chymotrypsin / Q000378:metabolism; D004586:Electrophoresis; D008297:Male; D051379:Mice; D008961:Models, Structural; D008970:Molecular Weight; D009414:Nerve Growth Factors / Q000032:analysis* / Q000378:metabolism; D010434:Pepsin A / Q000378:metabolism; D010455:Peptides / Q000032:analysis; D013363:Submandibular Gland / Q000032:analysis*; D013820:Thermolysin / Q000378:metabolism; D014357:Trypsin / Q000378:metabolism
chemical_list: D009414:Nerve Growth Factors; D010455:Peptides; D002918:Chymotrypsin; D014357:Trypsin; D010434:Pepsin A; D013820:Thermolysin