Resumo

The bacteriophage UFV-P2 is a virus with a high ability to reduce casein proteolysis caused by thermoresistant enzymes produced by Pseudomonas fluorescens. It is necessary to understand phages’ genome and proteome to make possible their use as biocontrol agents. Thus, we propose a new analysis of the UFV-P2 based on the sequence of the Pseudomonas phage LUZ24 genome. UFV-P2 genome was sequenced using an Illumina Genome Analyzer II and was assembled and analyzed using CLC Genomics Workbench version 5.1 (CLC bio, Cambridge, MA, USA). The genome of phage UFV-P2 was oriented to be collinear with that of the type species, Pseudomonas phage LUZ24, and manually annotated using specific softwares of sequence alignment, according to reference sequences in GenBank. The phage UFV-P2 has a linear 45,517 bp DNA genome with a GC content of 51.5% and a bidirectional organization with 75 ORFs forming clusters of early and late transcription, including seven promoters and three rho-independent transcription terminators. Fifty-five genes involved in nucleotide biosynthesis and viral replication (early genes) were found, which encodes for replication enzymes including the two exons of the viral DNA polymerase, between which there is a putative holin. In addition, the UFV-P2 genome contains a HNH endonuclease, which may be related to the presence of introns in the genome. Other enzymes include an amidoligase, a glutamine amidotransferase and an ATP-grasp enzyme. Twenty genes related to the assembly of the viral particle, DNA packaging, and host lysis were found in the negative strand (late genes). Between then are included the terminase subunits, which are the motor component that assists the translocation of viral genomic DNA to the inner of the capsid and could determine the points for cleavage of the viral DNA, influencing the entire viral genome organization. Other genes in this module are the portal protein, the major head protein, a scaffolding protein, the tail fiber protein, beyond a lysozyme, that is used in the process of host cell breakage through the lysis of the peptidoglycan layer. The occurrence of a lysin, not associated with its cognate holin, is unusual but also found in other members of the Luz24likevirus genus.