title: [Structure and biological properties of a conjugate of Bowman-Birk type soy proteinase inhibitor with a block copolymer of ethylene oxide and propylene oxide].
abstract: The structure of the conjugate of Bowman-Birk soybean proteinase inhibitor (BBI) with the block copolymer of ethylene oxide and propylene oxide (proxanol) containing five moles of proxanol per mole of protein, has been studied. Data from reverse phase hydrophobic HPLC suggest that the conjugate is less hydrophobic compared to native BBI. A shift of the second derivative UV absorption spectrum for the conjugate towards the shortwave region indicates a greater accessibility of the Tyr-59 residue localized in the interdomain region of the BBI molecule for the solvent. It has been assumed that the conjugate-induced increase in Ki for chymotrypsin may be due to both disturbances in the intact structure of the interdomain region of BBI and screening of the anti-chymotrypsin reactive center as a result of hydrophobic interactions of propylene oxide blocks of proxanol with exposed hydrophobic groups around the reactive center. Supporting evidence in favour of BBI molecule hydrophilization as a result of modification by proxanol can be derived from decreased conjugate penetration into intestinal epithelial cells as well as from the slow elimination of the conjugate from mouse blood stream.
authors.affiliation: University of Southern California, School of Pharmacy, Los Angeles, 90033, USA.
authors.forename: I P
authors.initials: IP
authors.lastname: Gladysheva
authors.forename: O V
authors.initials: OV
authors.lastname: Polekhina
authors.forename: W C
authors.initials: WC
authors.lastname: Shen
authors.forename: A A
authors.initials: AA
authors.lastname: Shevchenko
authors.forename: N F
authors.initials: NF
authors.lastname: Kazanskaia
authors.forename: N I
authors.initials: NI
authors.lastname: Larionova
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D002918:Chymotrypsin / Q000037:antagonists & inhibitors / Q000378:metabolism; D008297:Male; D051379:Mice; D015394:Molecular Structure; D011095:Polyethylenes / Q000737:chemistry* / Q000494:pharmacology; D011126:Polypropylenes / Q000737:chemistry* / Q000494:pharmacology; D013056:Spectrophotometry, Ultraviolet; D014358:Trypsin Inhibitor, Bowman-Birk Soybean / Q000097:blood / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D011095:Polyethylenes; D011126:Polypropylenes; D014358:Trypsin Inhibitor, Bowman-Birk Soybean; C078661:UCON 50-HB-5100; D002918:Chymotrypsin
vernacular_title: Stroenie i biologicheskie svoĭstva kon''iugata soevogo ingibitora proteinaz tipa Baumana-Birk s blok-sopolimerov okisi étilena i okisi propilena.