title: Functional identification of the DNA packaging terminase from Pseudomonas aeruginosa phage PaP3.
abstract: Terminase proteins are responsible for DNA recognition and initiation of DNA packaging in phages. We previously reported the genomic sequence of a temperate Pseudomonas aeruginosa phage, PaP3, and determined its precise integration site in the host bacterial chromosome. In this study, we present a detailed functional identification of the DNA packaging terminase for phage PaP3. The purified large subunit p03 was demonstrated to possess ATPase and nuclease activities, as well as the ability to bind to specific DNA when it is unassembled. In addition, a small terminase subunit (p01) of a new type was found and shown to bind specifically to cos-containing DNA and stimulate the cos-cleavage and ATPase activities of p03. The results presented here suggest that PaP3 utilizes a typical cos site mechanism for DNA packaging and provide a first step towards understanding the molecular mechanism of the PaP3 DNA packaging reaction.
authors.affiliation: Department of Microbiology, Third Military Medical University, Chongqing, China.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Shen
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Yijun
authors.initials: Y
authors.lastname: Zeng
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Hu
authors.forename: Yinling
authors.initials: Y
authors.lastname: Tan
authors.forename: Xiancai
authors.initials: X
authors.lastname: Rao
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Jin
authors.forename: Shu
authors.initials: S
authors.lastname: Li
authors.forename: Junmin
authors.initials: J
authors.lastname: Zhu
authors.forename: Kebin
authors.initials: K
authors.lastname: Zhang
authors.forename: Fuquan
authors.initials: F
authors.lastname: Hu
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism; D042003:DNA Packaging; D004279:DNA, Viral / Q000378:metabolism; D003851:Deoxyribonucleases / Q000235:genetics / Q000378:metabolism; D004706:Endodeoxyribonucleases / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D017105:Pseudomonas Phages / Q000201:enzymology* / Q000235:genetics / Q000502:physiology*; D011550:Pseudomonas aeruginosa / Q000821:virology
chemical_list: D004279:DNA, Viral; D003851:Deoxyribonucleases; D004706:Endodeoxyribonucleases; C030894:terminase; D000251:Adenosine Triphosphatases