scholarly journals The Characterization of a Novel Phage, pPa_SNUABM_DT01, Infecting Pseudomonas aeruginosa

2021 ◽  
Vol 9 (10) ◽  
pp. 2040
Author(s):  
Jun Kwon ◽  
Sang Wha Kim ◽  
Sang Guen Kim ◽  
Jeong Woo Kang ◽  
Won Joon Jung ◽  
...  

The bacterial genus Pseudomonas is a common causative agent of infections in veterinary medicine. In this study, we focused on Pseudomonas aeruginosa canine otitis externa isolates. Due to prolonged antibiotic treatment of otitis externa, antibiotic resistance is common and has become a major complication. Many alternatives to antibiotics have been studied, with bacteriophages emerging as the most promising alternatives. Here, we isolated and characterized a novel phage, pPa_SNUABM_DT01, by investigating its morphology, growth, lysis kinetics, and genomic characteristics. Phages have a vigorous capacity to eliminate bacterial cells through bacterial lysis. This capacity is dependent on the multiplicity of infection (MOI), but even at low MOIs, the phage successfully inhibited bacterial regrowth. The phage genome was 265,520 bp in size and comprised 312 putative open reading frames (ORFs). Comparative genome analysis demonstrated that the phage is a novel species in Myoviridae. The nucleotide similarity was moderately high compared with the Pseudomonas virus, Noxifer. However, a phylogenetic analysis and a dot plot indicated that pPa_SNUABM_DT01 is not closely related to the Phikzvirus or Noxifervirus genus but, instead, belongs to a novel one. The genome comparisons also indicate that the phage, pPa_SNUABM_DT01, could be a novel genus.

2021 ◽  
Author(s):  
Ruo-bin Lu ◽  
Ping-xiu Lan ◽  
Ru-jing Kang ◽  
Guan-lin Tan ◽  
Xiao-jiao Chen ◽  
...  

Abstract A novel enamovirus was identified from bean plants with disease symptoms. Its genome of 5,781 nucleotides (nt) encodes five open reading frames. The virus and other species of the genus Enamovirus share identities of 50.4%-68.4% at the complete genome, and 19.9%-51.9% of P0, 24.9%-52.5% of P1, 33.4%-62.9% of P1-P2, 30.6%-81.1% of P3, 32.3%-74.2% of P3-P5 at amino acid sequence level, respectively. Phylogenetic analysis showed that the virus is most closely related to Alfalfa enamovirus 1 and Pea enation mosaic virus 1 in the genus Enamovirus within family Solemoviridae. These results suggest that the virus should be considered as a novel species in the genus Enamovirus and tentatively named as “bean enamovirus 1”.


2018 ◽  
Vol 81 (7) ◽  
pp. 1117-1125 ◽  
Author(s):  
MENGZHE LI ◽  
YANQIU JIN ◽  
HONG LIN ◽  
JINGXUE WANG ◽  
XIUPING JIANG

ABSTRACT Vibrio parahaemolyticus is an important foodborne pathogen that is generally transmitted via raw or undercooked seafood. Endolysins originating from bacteriophages offer a new way to control bacterial pathogens. The objectives of this study were to sequence a novel lytic V. parahaemolyticus phage VPp1 and determine the antibacterial activities of the recombinant endolysin (LysVPp1) derived from this phage. The complete VPp1 genome contained a double-stranded DNA of 50,431 bp with a total G+C content of 41.35%. The genome was predicted to encode 67 open reading frames (ORFs), which were organized as nucleotide metabolism, replication, structure, packaging, lysis, and some additional functions. Two tRNAs were encoded to carry anticodons UGG and CCA. Among the functional proteins, ORF33 was deduced to encode endolysin, whereas no holin/antiholin or Rz/Rz1 lysis gene equivalents were found in the VPp1 genome. ORF33 was cloned and expressed. The endolysin LysVPp1 could lyse 9 of 12 V. parahaemolyticus strains, showing its relatively broader host spectrum than phage VPp1, which lysed only 3 of 12 V. parahaemolyticus strains. Furthermore, for EDTA-pretreated bacterial cells, the optical density of the LysVPp1 treatment group decreased by 0.4 at 450 nm, compared with less than 0.1 in control groups, demonstrating enhanced hydrolytic properties. These results contribute to the potential for development of novel enzybiotics for controlling V. parahaemolyticus.


1996 ◽  
Vol 40 (5) ◽  
pp. 1254-1256 ◽  
Author(s):  
H Hächler ◽  
P Santanam ◽  
F H Kayser

A novel, probably chromosomally encoded, aminoglycoside phosphotransferase gene was cloned on a 2,996-bp PstI fragment from Pseudomonas aeruginosa and designated aph (3')-IIb. It coded for a protein of 268 amino acids that showed 51.7% amino acid identity with APH (3')-II [APH(3') is aminoglycoside-3' phosphotransferase] from Tn5. Two other open reading frames on the cloned fragment showed homology to a signal-transducing system in P. aeruginosa.


1999 ◽  
Vol 65 (3) ◽  
pp. 951-960 ◽  
Author(s):  
Jörg Overhage ◽  
Andreas U. Kresse ◽  
Horst Priefert ◽  
Horst Sommer ◽  
Gerhard Krammer ◽  
...  

ABSTRACT Pseudomonas sp. strain HR199 is able to utilize eugenol (4-allyl-2-methoxyphenol), vanillin (4-hydroxy-3-methoxybenzaldehyde), or protocatechuate as the sole carbon source for growth. Mutants of this strain which were impaired in the catabolism of vanillin but retained the ability to utilize eugenol or protocatechuate were obtained after nitrosoguanidine mutagenesis. One mutant (SK6169) was used as recipient of a Pseudomonas sp. strain HR199 genomic library in cosmid pVK100, and phenotypic complementation was achieved with a 5.8-kbp EcoRI fragment (E58). The amino acid sequences deduced from two corresponding open reading frames (ORF) identified on E58 revealed high degrees of homology to pcaGand pcaH, encoding the two subunits of protocatechuate 3,4-dioxygenase. Three additional ORF most probably encoded a 4-hydroxybenzoate 3-hydroxylase (PobA) and two putative regulatory proteins, which exhibited homology to PcaQ of Agrobacterium tumefaciens and PobR of Pseudomonas aeruginosa, respectively. Since mutant SK6169 was also complemented by a subfragment of E58 that harbored only pcaH, this mutant was most probably lacking a functional β subunit of the protocatechuate 3,4-dioxygenase. Since this mutant was still able to grow on protocatechuate and lacked protocatechuate 4,5-dioxygenase and protocatechuate 2,3-dioxygenase, the degradation had to be catalyzed by different enzymes. Two other mutants (SK6184 and SK6190), which were also impaired in the catabolism of vanillin, were not complemented by fragment E58. Since these mutants accumulated 3-carboxy muconolactone during cultivation on eugenol, they most probably exhibited a defect in a step of the catabolic pathway following the orthocleavage. Moreover, in these mutants cyclization of 3-carboxymuconic acid seems to occur by a syn absolute stereochemical course, which is normally only observed forcis,cis-muconate lactonization in pseudomonads. In conclusion, vanillin is degraded through theortho-cleavage pathway in Pseudomonas sp. strain HR199 whereas protocatechuate could also be metabolized via a different pathway in the mutants.


Viruses ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 327
Author(s):  
Kristin Köppen ◽  
Grisna I. Prensa ◽  
Kerstin Rydzewski ◽  
Hana Tlapák ◽  
Gudrun Holland ◽  
...  

Here we present the characterization of a Francisella bacteriophage (vB_FhiM_KIRK) including the morphology, the genome sequence and the induction of the prophage. The prophage sequence (FhaGI-1) has previously been identified in F. hispaniensis strain 3523. UV radiation induced the prophage to assemble phage particles consisting of an icosahedral head (~52 nm in diameter), a tail of up to 97 nm in length and a mean width of 9 nm. The double stranded genome of vB_FhiM_KIRK contains 51 open reading frames and is 34,259 bp in length. The genotypic and phylogenetic analysis indicated that this phage seems to belong to the Myoviridae family of bacteriophages. Under the conditions tested here, host cell (Francisella hispaniensis 3523) lysis activity of KIRK was very low, and the phage particles seem to be defective for infecting new bacterial cells. Nevertheless, recombinant KIRK DNA was able to integrate site-specifically into the genome of different Francisella species after DNA transformation.


1999 ◽  
Vol 181 (14) ◽  
pp. 4275-4284 ◽  
Author(s):  
C. R. Dean ◽  
C. V. Franklund ◽  
J. D. Retief ◽  
M. J. Coyne ◽  
K. Hatano ◽  
...  

ABSTRACT We previously cloned a genomic DNA fragment from the serogroup O11Pseudomonas aeruginosa strain PA103 that contained all genes necessary for O-antigen synthesis and directed the expression of serogroup O11 antigen on recombinant Escherichia coli andSalmonella. To elucidate the pathway of serogroup O11 antigen synthesis, the nucleotide sequence of the biosynthetic genes was determined. Eleven open reading frames likely to be involved in serogroup O11 O-antigen biosynthesis were identified and are designated in order as wzz PaO111 (wzz fromP. aeruginosa serogroup O11),wzx PaO11, wbjA,wzy PaO11, wbjB to wbjF,wbpL O11 and wbpM O11(wbpL and wbpM from serogroup O11). Consistent with previous descriptions of O-antigen biosynthetic gene loci, the entire region with the exception of wbpM O11 has a markedly reduced G+C content relative to the chromosomal average. WzyPaO11 shows no significant similarity at the protein or DNA sequence level to any database sequence and is very hydrophobic, with 10 to 12 putative transmembrane domains, both typical characteristics of O-antigen polymerases. A nonpolar chromosomal insertion mutation in wzy PaO11 in P. aeruginosa PA103 confirmed the identity of this gene. There is striking similarity between WbjBCDE and Cap(5/8)EFGL, involved in type 5 and type 8 capsule biosynthesis in Staphylococcus aureus. There is nearly total identity between wbpM O11and wbpM O5, previously shown by others to be present in all 20 P. aeruginosa serogroups. Using similarity searches, we have assigned functions to the proteins encoded by the PA103 O-antigen locus and present the potential steps in the pathway for the biosynthesis of P. aeruginosa serogroup O11 O antigen.


Viruses ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 27
Author(s):  
Jun Kwon ◽  
Sang Guen Kim ◽  
Hyoun Joong Kim ◽  
Sib Sankar Giri ◽  
Sang Wha Kim ◽  
...  

The increasing emergence of antimicrobial resistance has become a global issue. Therefore, many researchers have attempted to develop alternative antibiotics. One promising alternative is bacteriophage. In this study, we focused on a jumbo-phage infecting Salmonella isolated from exotic pet markets. Using a Salmonella strain isolated from reptiles as a host, we isolated and characterized the novel jumbo-bacteriophage pSal-SNUABM-04. This phage was investigated in terms of its morphology, host infectivity, growth and lysis kinetics, and genome. The phage was classified as Myoviridae based on its morphological traits and showed a comparatively wide host range. The lysis efficacy test showed that the phage can inhibit bacterial growth in the planktonic state. Genetic analysis revealed that the phage possesses a 239,626-base pair genome with 280 putative open reading frames, 76 of which have a predicted function and 195 of which have none. By genome comparison with other jumbo phages, the phage was designated as a novel member of Machinavirus composed of Erwnina phages.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Chaitanya Erady ◽  
Adam Boxall ◽  
Shraddha Puntambekar ◽  
N. Suhas Jagannathan ◽  
Ruchi Chauhan ◽  
...  

AbstractUncharacterized and unannotated open-reading frames, which we refer to as novel open reading frames (nORFs), may sometimes encode peptides that remain unexplored for novel therapeutic opportunities. To our knowledge, no systematic identification and characterization of transcripts encoding nORFs or their translation products in cancer, or in any other physiological process has been performed. We use our curated nORFs database (nORFs.org), together with RNA-Seq data from The Cancer Genome Atlas (TCGA) and Genotype-Expression (GTEx) consortiums, to identify transcripts containing nORFs that are expressed frequently in cancer or matched normal tissue across 22 cancer types. We show nORFs are subject to extensive dysregulation at the transcript level in cancer tissue and that a small subset of nORFs are associated with overall patient survival, suggesting that nORFs may have prognostic value. We also show that nORF products can form protein-like structures with post-translational modifications. Finally, we perform in silico screening for inhibitors against nORF-encoded proteins that are disrupted in stomach and esophageal cancer, showing that they can potentially be targeted by inhibitors. We hope this work will guide and motivate future studies that perform in-depth characterization of nORF functions in cancer and other diseases.


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