StudioG24SecL04Tpc5: Difference between revisions
From Proteopedia
Jump to navigationJump to search
No edit summary |
No edit summary |
||
| Line 20: | Line 20: | ||
===Invariable=== | ===Invariable=== | ||
Invariable Region:<scene name='StudioG24SecL04Tpc5/Invariable_regions/1'>IR</scene> | Invariable Region:<scene name='StudioG24SecL04Tpc5/Invariable_regions/1'>IR</scene> | ||
The small invariable regions within the variable region as well as the larger invariable domains C & N terminals are not antigenic in natural infections and tend to be conserved among different isolates of the organism. Conserved portions are probably responsible for the maintenance of the functional and molecular conformations of the VlsE. | |||
==Antigenicity== | ==Antigenicity== | ||
Antigenic diversity enables the spirochete to escape host defense mechanisms and maintain infection. The variable regions of the lp28 -1 gene cassette extend this ability to VlsE. It has been postulated that infection induces sequence changes and thus alters the antigenic properties’ of VlsE. The generation of new antigens is thought to occur through the exchange of DNA cassettes by the process of recombination. This recombination could potentially help spirochetes escape anti-body mediated attack. The Vlse gene cluster consists of the single VlsE and 15 silent cassettes upstream. Unidirectional gene conversion events between the silent cassettes and VlsE gene generate new Vls variants. By producing a myriad of VlsE varaints that do not effectively bind to ant-VlsE antibodies elicited by previous versions of the protein VlsE evades immune destruction. | |||
One of the invariable regions IR6, showed both the highest levels of antigenicity by the Hopps-Woods algorithm and amino acid seqence identify among Borrelia genospecies and strains. Thus it is the most immunodominate region and what allows for the persistent humoral response. Examination of IR6 by the immunoprecipitation with the rabbit anti-C6 antiserum and revealed that IR6 is exposed on VlsE surface. However, IR6 is not accessible to Ab on the outer membrane of the spirochete. | |||
<Structure load='1l8w' size='300' frame='true' align='right' caption='IR6:Immunodominate Region of VlsE' scene='StudioG24SecL04Tpc5/Ir6_highlight/3' /> | <Structure load='1l8w' size='300' frame='true' align='right' caption='IR6:Immunodominate Region of VlsE' scene='StudioG24SecL04Tpc5/Ir6_highlight/3' /> | ||