|Venkataram Prasad, B|
Submitted to: Journal of Structural Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/30/2002
Publication Date: 2/1/2003
Citation: Chen, R., Neill, J.D., Venkataram Prasad, B.V. Crystallization and preliminary crystallographic analysis of San Miguel sea lion virus: An animal calicivirus. Journal of Structural Biology. 2003. v. 141. p. 143-148. Interpretive Summary: Emerging or newly discovered viruses are becoming more of a threat to both human and animal health. Some of these viruses belong to the calicivirus family of viruses. The enteric caliciviruses, a group that includes viruses that infect man, cattle and swine, do not grow in cell cultures. The human enteric caliciviruses are a major cause of viral food poisoning, while the swine and cattle caliciviruses may be involved in diarrhea outbreaks in livestock herds. Because these viruses cannot be grown in the laboratory, they are difficult to study. To better understand the infection process, San Miguel sea lion viruses, caliciviruses that grow well in the laboratory, were studied. They are similar to the enteric caliciviruses and can be used as a model for studying mechanisms of virus replication and pathology. We have begun determining the structure of the virus particle. This work has shown that the San Miguel sea lion virus is similar to the human enteric caliciviruses. Further research efforts will now be directed toward understanding the virus particle in greater detail. This information will allow researchers to understand the infection process of the caliciviruses and may lead to the design of better vaccines for viral infections.
Technical Abstract: The Caliciviridae is a family of non-enveloped, icosahedral, positive-sense single-stranded RNA viruses. This family of viruses consists of both animal and human pathogens. Adapting human caliciviruses to cell culture has not been successful, whereas some animal caliciviruses, including San Miguel sea lion viruses, have been successfully propagated in different cell lines. Here we report the crystallization of San Miguel sea lion virus serotype 4 (SMSV4) and the preliminary X-ray crystallographic analysis of the crystals. SMSV4 have been crystallized using the hanging-drop method. These crystals diffracted to ~3 Å resolution using synchrotron radiation source. The whole data set was collected at liquid nitrogen temperature. Data processing of the diffraction patterns showed that SMSV crystals belong to I23 space group with cell dimensions a=b=c=457.038Å. The crystallographic asymmetric unit includes five icosahedral asymmetric units, each consisting of three capsid protein subunits. In the space group I23, given the icosahedral symmetry and the size of the virus particle, the location of the particle is constrained to be at the point where the crystallographic 2- and 3-fold axes intersect. The orientation of the virus particle in the unit cell was ascertained by self-rotation function calculations.