G14secL04Tpc3: Difference between revisions
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on this loop. This important lysine forms an ionic salt bridge with the <scene name='G14secL04Tpc3/Lysine-253_and_glu50/2'>glutamic acid at residue 50</scene> | on this loop. This important lysine forms an ionic salt bridge with the <scene name='G14secL04Tpc3/Lysine-253_and_glu50/2'>glutamic acid at residue 50</scene> | ||
on the heavy chain of the antibody Fab Fragment. Thus, formation of the complex consists of the C-terminus of the OspB protein coming into contact with the variable regions of the H6831 antibody Fab fragment and the lysine-253 wedging between the two <scene name='G14secL04Tpc3/Lysine-253_glu50_tyr_and_trp/2'>aromatic residues</scene> | on the heavy chain of the antibody Fab Fragment. Thus, formation of the complex consists of the C-terminus of the OspB protein coming into contact with the variable regions of the H6831 antibody Fab fragment and the lysine-253 wedging between the two <scene name='G14secL04Tpc3/Lysine-253_glu50_tyr_and_trp/2'>aromatic residues</scene> | ||
(tryptophan-33 and tyrosine-101) and salt bridging with the glu-50 on the heavy chain of the antibody<ref name ="1rjl_pdb" />. Studies show that other bacterial strains having a cysteine, glycine, glutamic acid, or threonine in place of Lys-253 demonstrate resistance to the bactericidal effects of H6831 and also less binding affinity for the antibody Fab fragment <ref>A Sadziene, M Jonsson, S Bergström, R K Bright, R C Kennedy and A G Barbour. Infect. Immun. 1994, 62(5):2037. http://iai.asm.org/content/62/5/2037.short</ref>. This bolsters how important the Lys-253 is in the binding between the OspB protein and the antibody. Additionally, one report found that an ospB escape mutant in a population of infectious ''B. burgdorferi'', with a single base change in the ribosomal binding sequence and a single nucleotide deletion in the open reading frame of the ospB gene, demonstrated reduced expression and truncation of the OspB protein<ref name ="30_Sadziene"> A Sadziene, A G Barbour, P A Rosa and D D Thomas. Infect. Immun. 1993, 61(9):3590. http://iai.asm.org/content/61/9/3590.short</ref>. This reduced expression and truncation of OspB extenuated the penetration capability and infectivity of the spirochete in the human umbilical vein endothelium cells<ref name = "30_Sadziene" />. Thus, the OspB protein plays a fairly important role in the ability of the spirochete to infect a host, given that when it is damaged the spirochete's ability to infect the host is mitigated. After the complex is formed and the first four beta strands are cleaved off, a relic of this loss is a single <scene name='G14secL04Tpc3/Freely_floating_beta_strand/2'>freely floating beta strand</scene> on the N-terminus of the protein. This beta strand plays a role in the formation of dimers of OspB∙H6831 complex <ref name="1rjl_pdb" /> . Although the middle loop bearing the lysine is very important, the other loops certainly contribute to the bonding between OspB and the antibody fab fragment. For example, a <scene name='G14secL04Tpc3/Threonine_and_light_chain/1'>threonine</scene> | (tryptophan-33 and tyrosine-101) and salt bridging with the glu-50 on the heavy chain of the antibody<ref name ="1rjl_pdb" />. Studies show that other bacterial strains having a cysteine, glycine, glutamic acid, or threonine in place of Lys-253 demonstrate resistance to the bactericidal effects of H6831 and also less binding affinity for the antibody Fab fragment <ref>A Sadziene, M Jonsson, S Bergström, R K Bright, R C Kennedy and A G Barbour. Infect. Immun. 1994, 62(5):2037. http://iai.asm.org/content/62/5/2037.short</ref>. This bolsters how important the Lys-253 is in the binding between the OspB protein and the antibody. Additionally, one report found that an ospB escape mutant in a population of infectious ''B. burgdorferi'', with a single base change in the ribosomal binding sequence and a single nucleotide deletion in the open reading frame of the ospB gene, demonstrated reduced expression and truncation of the OspB protein<ref name ="30_Sadziene"> A Sadziene, A G Barbour, P A Rosa and D D Thomas. Infect. Immun. 1993, 61(9):3590. http://iai.asm.org/content/61/9/3590.short</ref>. This reduced expression and truncation of OspB extenuated the penetration capability and infectivity of the spirochete in the human umbilical vein endothelium cells<ref name = "30_Sadziene" />. Thus, the OspB protein plays a fairly important role in the ability of the spirochete to infect a host, given that when it is damaged the spirochete's ability to infect the host is mitigated. After the complex is formed and the first four beta strands are cleaved off, a relic of this loss is a single <scene name='G14secL04Tpc3/Freely_floating_beta_strand/2'>freely floating beta strand</scene> on the N-terminus of the protein. This beta strand plays a role in the formation of dimers of OspB∙H6831 complex <ref name="1rjl_pdb" /> during crystallization. Although the middle loop bearing the lysine is very important, the other loops certainly contribute to the bonding between OspB and the antibody fab fragment. For example, a <scene name='G14secL04Tpc3/Threonine_and_light_chain/1'>threonine</scene> | ||
at residue 276 on another loop interacts with residues on the light chain of the antibody fragment. | at residue 276 on another loop interacts with residues on the light chain of the antibody fragment. | ||
