G18secL03Tpc4: Difference between revisions
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is one of the major [http://en.wikipedia.org/wiki/Antigen antigens] on the surface of the [http://en.wikipedia.org/wiki/Lyme_disease Lyme disease] [http://en.wikipedia.org/wiki/Spirochaete spirochete], [http://en.wikipedia.org/wiki/Borrelia_burgdorferi ''Borrelia burgdorferi''], along with other outer surface proteins A and B ([http://www.proteopedia.org/wiki/index.php/OspA OspA] and [http://www.proteopedia.org/wiki/index.php/User:Marvin_O%27Neal/Antibody_OspA_and_OspB OspB], respectively). It greatly differs from OspA and OspB in both structure and function. The uniqueness of OspC is that it comes into play when the pathogen is being transmitted to humans or other mammals.OspC is critical for survival in or transmission to the tick or mammalian host.<ref>PMID:11169111</ref> OspC is being produced by ''Borrelia burgdorferi'' during a very short time interval when infected ticks start feeding, but its synthesis is known to slow down greatly after transmission to a mammalian host. Interestingly, when an infested tick engorges, ''B. burgdorferi'' within the gut multiply and downregulate ospA. At the same time, the spirochetes start producing OspC in the feeding gut and continue to produce OspC throughout the transmission process and during the establishment of early vertebrate infection. This pattern of expression suggests that OspC may serve a function in the tick, possibly facilitating the migration of the spirochete from the vector gut to the salivary glands during transmission. After transmission from the tick, OspC may also play a role in colonization of host tissues.<ref>PMID:14722614</ref> It was demonstrated that those spirochetes that lack OspC are capable to replicate inside and migrate to the salivary glands of the tick vector but do not infect mammals. <ref name="Kum">D. Kumaran1, S. Eswaramoorthy1, B.J. Luft2, S. Koide3, J.J. Dunn1, C.L. Lawson1,4 and S. Swaminathan1. Crystal structure of outer surface protein C (OspC) from the Lyme disease spirochete, Borrelia burgdorferi.The EMBO Journal (2001) 20, 971 - 978 [http://dx.doi.org/DOI:10.1093/emboj/20.5.971]</ref> Without OspC the spirochetes are believed to be unable to adapt to the environment inside the host. Therefore, OspC is believed to determine [http://en.wikipedia.org/wiki/Virulence virulence] of the spirochete to mammals, including humans. | is one of the major [http://en.wikipedia.org/wiki/Antigen antigens] on the surface of the [http://en.wikipedia.org/wiki/Lyme_disease Lyme disease] [http://en.wikipedia.org/wiki/Spirochaete spirochete], [http://en.wikipedia.org/wiki/Borrelia_burgdorferi ''Borrelia burgdorferi''], along with other outer surface proteins A and B ([http://www.proteopedia.org/wiki/index.php/OspA OspA] and [http://www.proteopedia.org/wiki/index.php/User:Marvin_O%27Neal/Antibody_OspA_and_OspB OspB], respectively). It greatly differs from OspA and OspB in both structure and function. The uniqueness of OspC is that it comes into play when the pathogen is being transmitted to humans or other mammals.OspC is critical for survival in or transmission to the tick or mammalian host.<ref>PMID:11169111</ref> OspC is being produced by ''Borrelia burgdorferi'' during a very short time interval when infected ticks start feeding, but its synthesis is known to slow down greatly after transmission to a mammalian host. Interestingly, when an infested tick engorges, ''B. burgdorferi'' within the gut multiply and downregulate ospA. At the same time, the spirochetes start producing OspC in the feeding gut and continue to produce OspC throughout the transmission process and during the establishment of early vertebrate infection. This pattern of expression suggests that OspC may serve a function in the tick, possibly facilitating the migration of the spirochete from the vector gut to the salivary glands during transmission. After transmission from the tick, OspC may also play a role in colonization of host tissues.<ref>PMID:14722614</ref> It was demonstrated that those spirochetes that lack OspC are capable to replicate inside and migrate to the salivary glands of the tick vector but do not infect mammals. <ref name="Kum">D. Kumaran1, S. Eswaramoorthy1, B.J. Luft2, S. Koide3, J.J. Dunn1, C.L. Lawson1,4 and S. Swaminathan1. Crystal structure of outer surface protein C (OspC) from the Lyme disease spirochete, Borrelia burgdorferi.The EMBO Journal (2001) 20, 971 - 978 [http://dx.doi.org/DOI:10.1093/emboj/20.5.971]</ref> Without OspC the spirochetes are believed to be unable to adapt to the environment inside the host. Therefore, OspC is believed to determine [http://en.wikipedia.org/wiki/Virulence virulence] of the spirochete to mammals, including humans. | ||
=== Basic Structure Description === | === Basic Structure Description === | ||
OspC proteins are highly [http://en.wikipedia.org/wiki/Polymorphism_(biology) polymorphic] and this variability extends even to strains collected from a single geographical area. <ref name="Kum"/> <Structure load='1ggq' size='400' frame='true' align='right' caption=' ' scene=' | OspC proteins are highly [http://en.wikipedia.org/wiki/Polymorphism_(biology) polymorphic] and this variability extends even to strains collected from a single geographical area. <ref name="Kum"/> <Structure load='1ggq' size='400' frame='true' align='right' caption=' ' scene='G18secL03Tpc4/2picfromtop/1'/> The outer surface protein C (ospC) locus ''Borrelia burgdorferi'' is at least an order of magnitude more variable than other genes in the species.<ref name="Brisson">PMID:15514047</ref> | ||
*Primary Structure | *Primary Structure | ||
The ospC gene is located on a 27 kb [http://en.wikipedia.org/wiki/Plasmid circular plasmid] and encodes a [http://en.wikipedia.org/wiki/Lipoprotein lipoprotein] of 22–23 kDa.<ref>PMID:7679385</ref> The protein is initially synthesized with an 18-amino-acid-long signal sequence which is removed during processing and [http://en.wiktionary.org/wiki/lipidated lipidation] at the amino proximal Cys residue. Each unit contains 162 amino acid residues. | The ospC gene is located on a 27 kb [http://en.wikipedia.org/wiki/Plasmid circular plasmid] and encodes a [http://en.wikipedia.org/wiki/Lipoprotein lipoprotein] of 22–23 kDa.<ref>PMID:7679385</ref> The protein is initially synthesized with an 18-amino-acid-long signal sequence which is removed during processing and [http://en.wiktionary.org/wiki/lipidated lipidation] at the amino proximal Cys residue. Each unit contains 162 amino acid residues. | ||