2B5B

A reptilian defensin with anti-bacterial and anti-viral activity

Summary for 2B5B

• Entry DOI: 10.2210/pdb2b5b/pdb
• Related: 1kj6
• Descriptor: Defensin (1 entity in total)
• Functional Keywords: antibiotic
• Biological source: Caretta caretta (Loggerhead turtle)
• Total number of polymer chains: 1
• Total formula weight: 4091.03

Authors

Chattopadhyay, S.,Sinha, N.K.,Banerjee, S.,Roy, D.,Chattopadhyay, D.,Roy, S. (deposition date: 2005-09-28, release date: 2006-06-27, Last modification date: 2024-10-16)

Primary citation

Chattopadhyay, S.,Sinha, N.K.,Banerjee, S.,Roy, D.,Chattopadhyay, D.,Roy, S.
Small cationic protein from a marine turtle has beta-defensin-like fold and antibacterial and antiviral activity.
Proteins, 64:524-531, 2006

PubMed Abstract: Egg white of marine turtle Caretta caretta contains a small cationic protein but lacks lysozyme. The protein was sequenced by a combination of sequential Edman degradation, carboxypeptidase digestion, nuclear magnetic resonance (NMR) and electrospray ionization tandem mass spectrometry. The protein contains 36 amino acid residues of which six are half-cysteines. The three-dimensional structure of the protein was deduced from two-dimensional NMR experiments and was observed to be similar to vertebrate beta-defensins. However, disulfide connectivity is C1-C6/C2-C5/C3-C4; different from that of the vertebrate beta-defensins. The protein showed strong antibacterial activity against Escherichia coli and Salmonella typhimurium. The protein also showed significant antiviral activity against an enveloped rhabdovirus, Chandipura virus, which is an emerging human pathogen. This virus is also closely related to the vesicular stomatitis virus, whose growth was also inhibited. This small cationic protein is part of the innate immunity of this organism and replaces lysozyme in the egg. It has the potential to be developed as an antibacterial and antiviral agent.

PubMed: 16700051
DOI: 10.1002/prot.20963

Experimental method

SOLUTION NMR