Genome Sequence, Structural Proteins, and Capsid Organization of the Cyanophage Syn5: A "Horned" Bacteriophage of Marine Synechococcus

@article{citeulike:1211954, abstract = {Marine Synechococcus spp and marine Prochlorococcus spp are numerically dominant photoautotrophs in the open oceans and contributors to the global carbon cycle. Syn5 is a short-tailed cyanophage isolated from the Sargasso Sea on Synechococcus strain WH8109. Syn5 has been grown in WH8109 to high titer in the laboratory and purified and concentrated retaining infectivity. Genome sequencing and annotation of Syn5 revealed that the linear genome is 46,214 bp with a 237 bp terminal direct repeat. Sixty-one open reading frames (ORFs) were identified. Based on genomic organization and sequence similarity to known protein sequences within GenBank, Syn5 shares features with T7-like phages. The presence of a putative integrase suggests access to a temperate life cycle. Assignment of 11 ORFs to structural proteins found within the phage virion was confirmed by mass-spectrometry and N-terminal sequencing. Eight of these identified structural proteins exhibited amino acid sequence similarity to enteric phage proteins. The remaining three virion proteins did not resemble any known phage sequences in GenBank as of August 2006. Cryo-electron micrographs of purified Syn5 virions revealed that the capsid has a single "horn", a novel fibrous structure protruding from the opposing end of the capsid from the tail of the virion. The tail appendage displayed an apparent 3-fold rather than 6-fold symmetry. An 18 A resolution icosahedral reconstruction of the capsid revealed a T = 7 lattice, but with an unusual pattern of surface knobs. This phage/host system should allow detailed investigation of the physiology and biochemistry of phage propagation in marine photosynthetic bacteria.}, author = {Pope, Welkin H. and Weigele, Peter R. and Chang, Juan and Pedulla, Marisa L. and Ford, Michael E. and Houtz, Jennifer M. and Jiang, Wen and Chiu, Wah and Hatfull, Graham F. and Hendrix, Roger W. and King, Jonathan }, citeulike-article-id = {1211954}, doi = {http://dx.doi.org/10.1016/j.jmb.2007.02.046}, journal = {Journal of Molecular Biology}, posted-at = {2007-04-06 15:22:51}, priority = {2}, title = {Genome Sequence, Structural Proteins, and Capsid Organization of the Cyanophage Syn5: A "Horned" Bacteriophage of Marine Synechococcus}, url = {http://dx.doi.org/10.1016/j.jmb.2007.02.046}, volume = {In Press, Corrected Proof} }

TY - JOUR ID - citeulike:1211954 L3 - citeulike-article-id:1211954 TI - Genome Sequence, Structural Proteins, and Capsid Organization of the Cyanophage Syn5: A "Horned" Bacteriophage of Marine Synechococcus JF - Journal of Molecular Biology VL - In Press, Corrected Proof N2 - Marine Synechococcus spp and marine Prochlorococcus spp are numerically dominant photoautotrophs in the open oceans and contributors to the global carbon cycle. Syn5 is a short-tailed cyanophage isolated from the Sargasso Sea on Synechococcus strain WH8109. Syn5 has been grown in WH8109 to high titer in the laboratory and purified and concentrated retaining infectivity. Genome sequencing and annotation of Syn5 revealed that the linear genome is 46,214 bp with a 237 bp terminal direct repeat. Sixty-one open reading frames (ORFs) were identified. Based on genomic organization and sequence similarity to known protein sequences within GenBank, Syn5 shares features with T7-like phages. The presence of a putative integrase suggests access to a temperate life cycle. Assignment of 11 ORFs to structural proteins found within the phage virion was confirmed by mass-spectrometry and N-terminal sequencing. Eight of these identified structural proteins exhibited amino acid sequence similarity to enteric phage proteins. The remaining three virion proteins did not resemble any known phage sequences in GenBank as of August 2006. Cryo-electron micrographs of purified Syn5 virions revealed that the capsid has a single "horn", a novel fibrous structure protruding from the opposing end of the capsid from the tail of the virion. The tail appendage displayed an apparent 3-fold rather than 6-fold symmetry. An 18 A resolution icosahedral reconstruction of the capsid revealed a T = 7 lattice, but with an unusual pattern of surface knobs. This phage/host system should allow detailed investigation of the physiology and biochemistry of phage propagation in marine photosynthetic bacteria. AU - Pope, Welkin AU - Weigele, Peter AU - Chang, Juan AU - Pedulla, Marisa AU - Ford, Michael AU - Houtz, Jennifer AU - Jiang, Wen AU - Chiu, Wah AU - Hatfull, Graham AU - Hendrix, Roger AU - King, Jonathan UR - http://dx.doi.org/10.1016/j.jmb.2007.02.046 ER -