Jones RT, Shih DTB, Fujita TS, Song Y, Xiao H, Head C and Kluger R |
------>authors3_c=None ------>paper_class1=1 ------>Impact_Factor=None ------>paper_class3=2 ------>paper_class2=1 ------>vol=271 ------>confirm_bywho=cmbdshih ------>insert_bywho=??? ------>Jurnal_Rank=None ------>authors4_c=None ------>comm_author=0 ------>patent_EDate=None ------>authors5_c=None ------>publish_day=None ------>paper_class2Letter=None ------>page2=680 ------>medlineContent= ------>unit=E0600 ------>insert_date=19991209 ------>iam=2 ------>update_date= ------>author=??? ------>change_event=5 ------>ISSN=None ------>authors_c=None ------>score=453 ------>journal_name=J. Biol. Chem. ------>paper_name=A doubly cross-linked human hemoglobin effect of cross-linking between different subunits. ------>confirm_date=20010330 ------>tch_id=083001 ------>pmid=8557672 ------>page1=675 ------>fullAbstract=Human deoxyhemoglobin cross-linked with trimesyl tris(3,5-dibromosalicylate) produces the previously reported cross-linked hemoglobin in which the epsilon amino groups of the two beta chain 82 lysyl residues are joined by a trimesyl bridge. Further specific modification of this protein directed to the alpha subunits with bis(3,5-dibromosalicyl)fumarate gives a doubly cross-linked material in which the epsilon-amino groups of the two alpha chain 99 lysyl residues are now joined by a fumaryl bridge. The singly cross-linked beta chain species binds oxygen cooperatively with a high oxygen affinity (P50 = 4.8 torr at pH 7.4). The addition of the second cross-linking reduces the oxygen affinity to 15.9 torr, which compares with 13.0 torr for the singly cross-linked alpha chain species. The doubly cross-linked hemoglobin retains significant cooperativity with a Hill coefficient of 2.3 compared with 3.0 for unmodified hemoglobin. Because some of the groups responsible for the Bohr effect are acylated, this doubly cross-linked hemoglobin exhibits 25% of the normal Bohr effect and less than 20% of the normal chloride effect. The use of two distinct cross-links within the same tetramer provides a material for physical and structural analysis as well as for further modifications for specific applications. The results indicate that the cross-link introducing the lowest oxygen affinity in the two singly cross-linked species appears to control the overall affinity in this doubly cross-linked species. ------>tmu_sno=None ------>sno=575 ------>authors2=None ------>authors3=None ------>authors4=None ------>authors5=None ------>authors6=None ------>authors6_c=None ------>authors=Jones RT, Shih DTB, Fujita TS, Song Y, Xiao H, Head C and Kluger R ------>delete_flag=0 ------>SCI_JNo=None ------>authors2_c=None ------>publish_area=None ------>updateTitle=A doubly cross-linked human hemoglobin. Effects of cross-links between different subunits. ------>language= ------>check_flag=0 ------>submit_date= ------>country=None ------>no=2 ------>patent_SDate=None ------>update_bywho= ------>publish_year=1996 ------>submit_flag= ------>publish_month=None |