Periplasmic dipeptide-binding protein: Difference between revisions
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== General Information about DppA == | == General Information about DppA == | ||
Bacterial DppA proteins have signature Sec signal peptides specific to heme binding<ref name=Alex/>. Research indicates the Sec signal peptide present on DppA of Mtb must be present for heme binding to occur<ref name=Alex/>. DppA exhibits a much lower dissociation constant than other PBPs, around ~1.5 uM. This is significantly less than functionally similar proteins such as ''H. influenzae''’s HbpA or ''E. coli''’s DppA (HbpA<sub>''H. influenzae''<sub> = ~655 uM and DppA<sub>''E. coli''<sub> = ~10 uM)<ref name=Alex/>. | Bacterial DppA proteins have signature Sec signal peptides specific to heme binding<ref name=Alex/>. Research indicates the Sec signal peptide present on DppA of Mtb must be present for heme binding to occur<ref name=Alex/>. DppA exhibits a much lower dissociation constant than other PBPs, around ~1.5 uM. This is significantly less than functionally similar proteins such as ''H. influenzae''’s HbpA or ''E. coli''’s DppA (HbpA<sub>''H. influenzae''</sub> = ~655 uM and DppA<sub>''E. coli''<sub/> = ~10 uM)<ref name=Alex/>. | ||
== Crystal Structure of DppA == | == Crystal Structure of DppA == | ||
Crystal structure was obtained at 1.27Å resolution, with R <sub>work<sub> / free = 12.8/16.5%<ref name=Alex/>. The structure shows a globular, heart-like appearance. The tertiary structure is formed from two globular and mildly offset halves which are quite complementary. The two halves fold onto each other, similar to two shells of a mollusk. | Crystal structure was obtained at 1.27Å resolution, with R <sub>work</sub>/free = 12.8/16.5%<ref name=Alex/>. The structure shows a globular, heart-like appearance. The tertiary structure is formed from two globular and mildly offset halves which are quite complementary. The two halves fold onto each other, similar to two shells of a mollusk. | ||
== “Clothespin Spring” α-helical Hinge == | == “Clothespin Spring” α-helical Hinge == | ||
