Structural and functional analogy between pneumolysin and proaerolysin.

R Sowdhamini; T J Mitchell; P W Andrew; P J Morgan

doi:10.1093/protein/10.3.207

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Structural and functional analogy between pneumolysin and proaerolysin.

R Sowdhamini·T J Mitchell·P W Andrew·P J Morgan

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Abstract

Pneumolysin and proaerolysin are bacterial toxins that form pores in host cells by oligomerization. We propose that they may have similar structures despite a poor sequence identity. The crystal structure of proaerolysin reveals a protein composed of four domains, arranged in the shape of an elongated comma. Electron microscopy of the pneumolysin monomer shows a similar arrangement of domains. The sequence of pneumolysin recognizes the template of proaerolysin from a library of protein folds. A three-dimensional model of pneumolysin has been constructed by the comparative approach using the structure of proaerolysin. This model, together with results on the activity of site-specific mutants and the positions of antigenic sites, has been used to propose functional roles of individual domains.

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Amino Acid Sequence Bacterial Proteins Bacterial Toxins Crystallography, X-Ray Hemolysin Proteins Microscopy, Electron Models, Molecular Molecular Sequence Data Pore Forming Cytotoxic Proteins Protein Conformation Protein Folding Protein Structure, Secondary Sequence Alignment Software Streptolysins Structure-Activity Relationship Journal Article Research Support, Non-U.S. Gov't

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R Sowdhamini, T J Mitchell, P W Andrew, P J Morgan. 1997. Structural and functional analogy between pneumolysin and proaerolysin.. https://doi.org/10.1093/protein%2F10.3.207

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