SB2013 L04gr5: Difference between revisions
From Proteopedia
Jump to navigationJump to search
Julia Joseph (talk | contribs) No edit summary |
Emma Brower (talk | contribs) No edit summary |
||
| Line 11: | Line 11: | ||
The lipoprotein, VlsE, consists of two invariable domains at the amino and carboxyl termini and a variable domain (Figure 1). When referring to the primary structure of the protein, the variable domain is a cassette region located between the two termini. The variable domain can be further broken down into variable regions (<scene name='SB2013_L04gr5/Variable_regions/3'>VRs</scene>) and invariable regions (<scene name='SB2013_L04gr5/Invariable_regions/2'>IRs</scene>) <ref name="Liang" />. | The lipoprotein, VlsE, consists of two invariable domains at the amino and carboxyl termini and a variable domain (Figure 1). When referring to the primary structure of the protein, the variable domain is a cassette region located between the two termini. The variable domain can be further broken down into variable regions (<scene name='SB2013_L04gr5/Variable_regions/3'>VRs</scene>) and invariable regions (<scene name='SB2013_L04gr5/Invariable_regions/2'>IRs</scene>) <ref name="Liang" />. | ||
When crystallized, VlsE forms a four molecule asymmetric unit with each molecule having slight differences in their conformation. | When crystallized, VlsE forms a four molecule asymmetric unit with each molecule having slight differences in their conformation. Although each molecule in the unit is slightly different, a single molecule of the protein consists of eleven [http://en.wikipedia.org/wiki/Alpha_helices α-helices] and four short [http://en.wikipedia.org/wiki/Beta_strand β-strands]. Helices α1 (aa 306-341), α2 (aa 68-87), α3 (aa 114-139), and α11 (aa 306-341) all form the <scene name='SB2013_L04gr5/Membrane_proximal_region/1'>membrane proximal region</scene> of VlsE, while helices α4 (aa 161-176), α5 (aa 180-185), α6 (aa 195-201), α7 (aa 213-224), α8 (aa 228-239), α9 (aa 255-260) and α10 (aa 277-289) form the primary region of the <scene name='SB2013_L04gr5/Membrane_distal_region/2'>membrane distal region</scene> of the protein. The four short β-strands each consist of 3 amino acids and can also be located in the membrane distal region <ref name="Eicken" />. | ||
Covering the membrane distal part of VlsE are connecting loop regions, which lack secondary structure and have different conformations in each of the molecules. Helices α3 through α10 form the invariable regions and are attached by the connecting loops that are classified as the variable regions. Although VlsE crystallizes into an asymmetrical unit, it appears primarily as monomeric in solution. Because the interface between VlsE molecules in the crystal structure buries approximately 13% of the accessible surface area of the monomers, research suggests that there is a possibility of VlsE existing as a [http://en.wikipedia.org/wiki/Protein_dimer dimer] when in its natural state (Figure 2)<ref name="Eicken" />. <scene name='SB2013_L04gr5/Reset_button/1'>Reset</scene> | Covering the membrane distal part of VlsE are connecting loop regions, which lack secondary structure and have different conformations in each of the molecules. Helices α3 through α10 form the invariable regions and are attached by the connecting loops that are classified as the variable regions. Although VlsE crystallizes into an asymmetrical unit, it appears primarily as monomeric in solution. Because the interface between VlsE molecules in the crystal structure buries approximately 13% of the accessible surface area of the monomers, research suggests that there is a possibility of VlsE existing as a [http://en.wikipedia.org/wiki/Protein_dimer dimer] when in its natural state (Figure 2)<ref name="Eicken" />. <scene name='SB2013_L04gr5/Reset_button/1'>Reset</scene> | ||
| Line 55: | Line 55: | ||
==''N- and C- Terminal Regions''== | ==''N- and C- Terminal Regions''== | ||
In addition to the IR6 region, specific sequences of the N- and C- terminal invariable domains are known to be major B cell epitopes in Lyme disease patients. | In addition to the IR6 region, specific sequences of the N- and C- terminal invariable domains are known to be major B cell epitopes in Lyme disease patients. Although the N and C termini appeared to be flexible when crystallized<name ref:"Eickent" />, the crystal structure of VlsE indicates that the two sequences lie adjacent to each other, making them a single target covered by peptides VlsE21 through VlsE31 and VlsE336 through VlsE343.<ref name="Chandra" /> It has been found that antibodies that interact with this membrane-proximal part become more potent in later stages of infection. According to ELISA results, post Lyme disease syndrome patients exhibited much higher antibody activity at the epitopes than fully recovered patients. Therefore, detection of these antibodies are useful in patient follow-ups, especially with those experiencing the later stages of Lyme disease.<ref name="Chandra" /> | ||
=Conclusion= | =Conclusion= | ||
