G14secL04Tpc3: Difference between revisions
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form two sheets that bend, along with the final <scene name='G14secL04Tpc3/8-12_beta_strands_showing/2'>alpha-helix</scene> | form two sheets that bend, along with the final <scene name='G14secL04Tpc3/8-12_beta_strands_showing/2'>alpha-helix</scene> | ||
that comes over the top into the <scene name='G14secL04Tpc3/C-terminal_barrel_domain/4'>C-terminal barrel domain </scene> | that comes over the top into the <scene name='G14secL04Tpc3/C-terminal_barrel_domain/4'>C-terminal barrel domain </scene> | ||
. It has been shown that OspB deficient spirochetes lack the ability to bind to the tick gut<ref> http://www.plospathogens.org/article/info%3Adoi%2F10.1371%2Fjournal.ppat.0030033</ref>. Further studies suggest that the structural barrel domain is what gives OspB the ability to adhere to the tick gut wall. The barrel domain cavity could serve as the binding site for an exposed protein loop, small peptide, or linear saccharide hanging off the tick gut wall<ref name="1rjl_pdb">http://www.jbc.org/content/280/17/17363.full</ref>. <scene name='G14secL04Tpc3/1-4_beta_strands_showing/1'>Beta strands 1-4 </scene> on free OspB's N-terminus are cleaved when OspB is bound to antibody fragment H6831, suggesting that they're removed by the proteolysis in the H6831-bound complex<ref name = "1rjl_pdb" />. The OspB protein is an integral membrane lipoprotein, with its lipidated N-terminus imbedded in the outer membrane of the spirochete and its C-terminus directed away from the membrane<ref>http://iai.asm.org/content/58/4/983.short</ref>. | . It has been shown that OspB deficient spirochetes lack the ability to bind to the tick gut<ref> http://www.plospathogens.org/article/info%3Adoi%2F10.1371%2Fjournal.ppat.0030033</ref>. Further studies suggest that the structural barrel domain is what gives OspB the ability to adhere to the tick gut wall. The barrel domain cavity could serve as the binding site for an exposed protein loop, small peptide, or linear saccharide hanging off the tick gut wall<ref name="1rjl_pdb">http://www.jbc.org/content/280/17/17363.full</ref>. <scene name='G14secL04Tpc3/1-4_beta_strands_showing/1'>Beta strands 1-4 </scene> on free OspB's N-terminus are cleaved when OspB is bound to antibody fragment H6831, suggesting that they're removed by the proteolysis in the H6831-bound complex<ref name = "1rjl_pdb" />. The OspB protein is an integral membrane lipoprotein, with its lipidated N-terminus imbedded in the outer membrane of the spirochete and its C-terminus directed away from the membrane<ref>http://iai.asm.org/content/58/4/983.short</ref>. It is speculated that proteolytic action on these N-terminus beta strands somehow cause lysis of the spirochete. Studies have shown that when complement-independent antibodies such as H6831 act on OspB, the result is blebbing of the outer membrane of the bacteria <ref name="Blebbing">http://www.jstor.org/stable/40483625?&Search=yes&searchText=region&searchText=antibody&searchText=protein&searchText=directed&searchText=bactericidal&searchText=Borrelia&searchText=variable&searchText=burgdorferi&searchText=OspB&list=hide&searchUri=%2Faction%2FdoBasicSearch%3FQuery%3D%2BA%2Bbactericidal%2Bantibody%2Bto%2BBorrelia%2Bburgdorferi%2Bis%2Bdirected%2Bagainst%2Ba%2Bvariable%2Bregion%2Bof%2Bthe%2BOspB%2Bprotein%26acc%3Don%26wc%3Don&prevSearch=&item=3&ttl=7&returnArticleService=showFullText</ref>. This blebbing of the bacterial membrane has been shown to create small openings in the outer membrane of the bacteria, which leads for potential osmotic lysis depending on the solution the bacteria is in<ref name="Blebbing" />. | ||
==OspB complexed with H6831 Antibody Fab Fragment== | ==OspB complexed with H6831 Antibody Fab Fragment== | ||
