These parts of a host lysis cassette are every present within the genome of phages eiAU, eiDWF, and eiMSLS which includes a putative Rz lysis accessory protein encoded by ORF38. The RZ protein is predicted to be a style II integral membrane protein and its function, despite the fact that not fully understood, may very well be needed for host cell lysis only inside a medium con taining an excess of divalent cations. Phage endoly sins have been linked to 5 enzymatic activities, which include an N acetyl muramidase or correct lysosyme, the lytic transglycosylases, the N acetylmuramoyl L ala nine amidases, the endo b N acetylglucosaminidases, and also the endopeptidases. Secondary construction evaluation predicts that the endolysin of eiAU is actually a member with the N acetylmuramoyl L alanine amidases class of endolysins.
DNA replication proteins ORFs with considerable sequence similarity to proteins involved in DNA replication were recognized in all three E. ictaluri precise phage genomes. ORF44 is predicted to encode a phage replicative helicase primease. selleck chemicals Several phages use separate primase and helicase proteins whilst many others use a multifunctional protein possessing both pursuits. The helicase primase pro tein operates in DNA replication by unwinding double stranded DNA into single stranded DNA. No pre dicted function might be assigned to ORFs45 and 46. Also, no predicted function may be assigned to ORF47. how ever, a look for secondary structures inside of the pre dicted ORF47 amino acid sequence detected a helix hairpin helix DNA binding motif. In addition, no puta tive perform can be assigned to ORF48, ORF49, or ORF50.
ORF51 had as considered one of its top BLAST hits an iso prenylcysteine carboxyl methyltransferase known to func tion in methylating isoprenylated amino acids. ORF52 is predicted to encode a protein much like gp41 of Sodalis phage SO one, but no putative perform could be assigned. ORF53 is predicted to encode DNA polymerase I. Second ary structure examination somehow advised that the DNA polymerase encoded by ORF53 has a domain that is responsible for that 3 five exonuclease evidence studying action of E. coli DNA polymerase I along with other enzymes, and catalyses the hydrolysis of unpaired or mismatched nucleotides. The protein encoded by ORF54 is predicted to have a VUR NUC domain, which are linked with members from the PD XK nuclease superfamily such as sort III restric tion modification enzymes.
ORF2 is predicted to encode a DNA restore ATPase. A look for secondary structures inside the ORF2 predicted amino acid sequence unveiled a HNH endonuclease. No putative function could be assigned to ORF3. ORF4 is predicted to encode a helicase protein belonging on the SNF2 loved ones, typically uncovered in proteins involved within a assortment of processes together with tran scription regulation, DNA restore, DNA recombination, and chromatin unwinding. ORF6 is predicted to encode a phage methyltransferase. Secondary construction evaluation revealed the methyltransferase predicted to be encoded by ORF6 is a C five cytosine particular DNA methylase which in bacteria can be a component of restriction modification methods. Also, Mg and ATP binding web pages had been detected while in the predicted protein solution of ORF6. ORF7 is predicted to encode a DNA N six adenine methyl transferase inside of a family members of methyltransferase located in bacteria and phage that has web page unique DNA methyltrans ferase activity. No ORF encoding an RNA polymerase was detected in any in the phages suggesting that these phages count on the host RNA polymerase to transcribe their genes.