5Y2G
Structure of MBP tagged GBS CAMP
Summary for 5Y2G
| Entry DOI | 10.2210/pdb5y2g/pdb |
| Related PRD ID | PRD_900001 |
| Descriptor | Maltose-binding periplasmic protein,Protein B, alpha-D-glucopyranose-(1-4)-alpha-D-glucopyranose, SULFATE ION (3 entities in total) |
| Functional Keywords | camp factor, pore forming toxin, toxin |
| Biological source | Escherichia coli More |
| Total number of polymer chains | 1 |
| Total formula weight | 66132.56 |
| Authors | |
| Primary citation | Li, Y.,Zeng, W.,Li, Y.,Fan, W.,Ma, H.,Fan, X.,Jiang, J.,Brefo-Mensah, E.,Zhang, Y.,Yang, M.,Dong, Z.,Palmer, M.,Jin, T. Structure determination of the CAMP factor of Streptococcus agalactiae with the aid of an MBP tag and insights into membrane-surface attachment. Acta Crystallogr D Struct Biol, 75:772-781, 2019 Cited by PubMed Abstract: CAMP factor is a unique α-helical bacterial toxin that is known for its co-hemolytic activity in combination with staphylococcal sphingomyelinase. It was first discovered in the human pathogen Streptococcus agalactiae (also known as group B streptococcus), but homologous genes have been found in many other Gram-positive pathogens. In this study, the efforts that led to the determination of the first structure of a CAMP-family toxin are reported. Initially, it was possible to produce crystals of the native protein which diffracted to near 2.45 Å resolution. However, a series of technical obstacles were encountered on the way to structure determination. Over a period of more than five years, many methods, including selenomethionine labeling, mutations, crystallization chaperones and heavy-atom soaking, were attempted, but these attempts resulted in limited progress. The structure was finally solved using a combination of iodine soaking and molecular replacement using the crystallization chaperone maltose-binding protein (MBP) as a search model. Analysis of native and MBP-tagged CAMP-factor structures identified a conserved interaction interface in the C-terminal domain (CTD). The positively charged surface may be critical for binding to acidic ligands. Furthermore, mutations on the interaction interface at the CTD completely abolished its co-hemolytic activities. This study provides novel insights into the mechanism of the membrane-permeabilizing activity of CAMP factor. PubMed: 31373576DOI: 10.1107/S205979831901057X PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (3 Å) |
Structure validation
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