title: Characterization of two major isoforms of juvenile hormone esterase from Trichoplusia ni (Lepidoptera).
abstract: The two major isoforms of juvenile hormone (JH) esterase isolated from Trichoplusia ni were fragmented by cyanogen bromide and trypsin digestion. The resulting CNBr or CNBr/trypsin fragments were characterized and compared biochemically by SDS-PAGE, isoelectric focusing, two-dimensional electrophoresis and HPLC. Similar and unique fragments were examined for sequence, antigenic determinants and carbohydrate moieties. The studies identified small regions of the proteins which possess either potentially different sequences or different post-translational modifications. The location of a glycosylated asparagine residue was determined, as well as a region containing an epitope probably composed of a linear sequence of residues. An N-terminal region was identified that contained charge variation between the two isoforms and the sequence was obtained for the only unique CNBr/trypsin fragment detected from that region. These are the first data on mapping of regions of charge variation, epitope location and glycosylation sites for this enzyme from any insect species.
authors.affiliation: School of Biological Sciences, University of Kentucky, Lexington 40546.
authors.forename: G
authors.initials: G
authors.lastname: Jones
authors.forename: M
authors.initials: M
authors.lastname: Manczak
authors.forename: M
authors.initials: M
authors.lastname: Wozniak
authors.forename: R
authors.initials: R
authors.lastname: Ko'rrati
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002265:Carboxylic Ester Hydrolases / Q000737:chemistry / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D003488:Cyanogen Bromide; D004563:Electrochemistry; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes; D006031:Glycosylation; D007301:Insect Hormones / Q000737:chemistry / Q000378:metabolism*; D007527:Isoenzymes / Q000737:chemistry / Q000378:metabolism*; D007915:Lepidoptera / Q000201:enzymology*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000378:metabolism; D010449:Peptide Mapping; D017386:Sequence Homology, Amino Acid; D014357:Trypsin
chemical_list: D000939:Epitopes; D007301:Insect Hormones; D007527:Isoenzymes; D010446:Peptide Fragments; D002265:Carboxylic Ester Hydrolases; C038003:juvenile hormone esterase; D014357:Trypsin; D003488:Cyanogen Bromide