scholarly journals Characterization of Lytic Enzyme Open Reading Frame 9 (ORF9) Derived fromEnterococcus faecalisBacteriophage φEF24C

2010 ◽  
Vol 77 (2) ◽  
pp. 580-585 ◽  
Author(s):  
Jumpei Uchiyama ◽  
Iyo Takemura ◽  
Ikue Hayashi ◽  
Shigenobu Matsuzaki ◽  
Miho Satoh ◽  
...  
Keyword(s):  
Viable Count ◽  
Open Reading Frame ◽  
Lytic Enzyme ◽  
Ionization Time ◽  
Reading Frame ◽  
Gram Positive Bacteria ◽  
Flight Mass Spectrometry ◽  
Resistant Strains ◽  
Orf9 Protein

ABSTRACTIn bacteriophage (phage) therapy against Gram-positive bacteria, such asStaphylococcus aureus,Listeria monocytogenes, andEnterococcus faecalis, members of a genus of SPO1-like viruses are typically employed because of their extreme virulence and broad host spectrum. Phage φEF24C, which is a SPO1-like virus infectingE. faecalis, has previously been characterized as a therapeutic phage candidate. In addition to the phage itself, phage endolysin is also recognized as an effective antimicrobial agent. In this study, a putative endolysin gene (orf9) ofE. faecalisphage φEF24C was analyzedin silico, and its activity was characterized using the recombinant form. First, bioinformatics analysis predicted that the open reading frame 9 (ORF9) protein isN-acetylmuramoyl-l-alanine amidase. Second, bacteriolytic and bactericidal activities of ORF9 againstE. faecaliswere confirmed by zymography, decrease of peptidoglycan turbidity, decrease of the viable count, and morphological analysis of ORF9-treated cells. Third, ORF9 did not appear to require Zn2+ions for its activity, contrary to the bioinformatics prediction of a Zn2+ion requirement. Fourth, the lytic spectrum was from 97.1% (34 out of 35 strains, including vancomycin-resistant strains) ofE. faecalisstrains to 60% (6 out of 10 strains) ofEnterococcus faeciumstrains. Fifth,N-acetylmuramoyl-l-alanine amidase activity of ORF9 was confirmed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and the subsequent MALDI-postsource decay (PSD) analyses. Finally, functional analysis using N- or C-terminally deleted ORF9 mutants suggested that a complete ORF9 molecule is essential for its activity. These results suggested that ORF9 is an endolysin of phage φEF24C and can be a therapeutic alternative to antibiotics.

scholarly journals Antigenic Characterization of ORF2 and ORF3 Proteins of Hepatitis E Virus (HEV)

Viruses ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1385
Author(s):  
Giulia Pezzoni ◽  
Lidia Stercoli ◽  
Eleonora Pegoiani ◽  
Emiliana Brocchi
Keyword(s):  
Hepatitis E Virus ◽  
Hepatitis E ◽  
Recombinant Antigen ◽  
Open Reading Frame ◽  
Reading Frame ◽  
E Coli ◽  
Antigenic Characterization ◽  
Antigenic Properties ◽  
Open Reading Frame 2

To evaluate the antigenic properties of Hepatitis E Virus (HEV) Open Reading Frame 2 and 3 (ORF2 and ORF3) codified proteins, we expressed different portions of ORF2 and the entire ORF3 in E. coli, a truncated ORF2, was also expressed in baculovirus. A panel of 37 monoclonal antibodies (MAbs) was raised against ORF2 (1–660 amino acids) and MAbs were mapped and characterized using the ORF2 expressed portions. Selected HEV positive and negative swine sera were used to evaluate ORF2 and ORF3 antigens’ immunogenicity. The MAbs were clustered in six groups identifying six antigenic regions along the ORF2. Only MAbs binding to the sixth ORF2 antigenic region (394–608 aa) were found to compete with HEV positive sera and efficiently catch the recombinant antigen expressed in baculovirus. The ORF2 portion from 394–608 aa demonstrated to include most immunogenic epitopes with 85% of HEV positive swine sera reacting against the region from 461–544 aa. Only 5% of the selected HEV sera reacted against the ORF3 antigen.

scholarly journals Gene Cloning and Molecular Characterization of a Two-Enzyme System Catalyzing the Oxidative Detoxification of β-Endosulfan

2002 ◽  
Vol 68 (12) ◽  
pp. 6237-6245 ◽  
Author(s):  
Tara D. Sutherland ◽  
Irene Horne ◽  
Robyn J. Russell ◽  
John G. Oakeshott
Keyword(s):  
Shuttle Vector ◽  
Open Reading Frame ◽  
Cosmid Library ◽  
Flavin Mononucleotide ◽  
Flavin Reductase ◽  
Reading Frame ◽  
Reductase Gene ◽  
Degradation Activity ◽  
Layer Chromatography

ABSTRACT The gram-positive bacterium Mycobacterium sp. strain ESD is able to use the cyclodiene insecticide endosulfan as a source of sulfur for growth. This activity is dependent on the absence of sulfite or sulfate in the growth medium. A cosmid library of strain ESD DNA was constructed in a Mycobacterium-Escherichia coli shuttle vector and screened for endosulfan-degrading activity in Mycobacterium smegmatis, a species that does not degrade endosulfan. Using this method, we identified a single cosmid that conferred sulfur-dependent endosulfan-degrading activity on the host strain. An open reading frame (esd) was identified within this cosmid that, when expressed behind a constitutive promoter in a mycobacterial expression vector, conferred sulfite- and sulfate-independent β-endosulfan degradation activity on the recombinant strain. The translation product of this gene (Esd) had up to 50% sequence identity with an unusual family of monooxygenase enzymes that use reduced flavins, provided by a separate flavin reductase enzyme, as cosubstrates. An additional partial open reading frame was located upstream of the Esd gene that had sequence homology to the same monooxygenase family. A flavin reductase gene, identified in the M. smegmatis genome, was cloned, expressed, and used to provide reduced flavin mononucleotide for Esd in enzyme assays. Thin-layer chromatography and gas chromatography analyses of the enzyme assay mixtures revealed the disappearance of β-endosulfan and the appearance of the endosulfan metabolites, endosulfan monoaldehyde and endosulfan hydroxyether. This suggests that Esd catalyzes the oxygenation of β-endosulfan to endosulfan monoaldehyde and endosulfan hydroxyether. Esd did not degrade either α-endosulfan or the metabolite of endosulfan, endosulfan sulfate.

scholarly journals Cloning and characterization of α-pinene synthase from Chamaecyparis formosensis Matsum

Holzforschung ◽  
2009 ◽  
Vol 63 (1) ◽  
Author(s):  
Fang-Hua Chu ◽  
Pei-Min Kuo ◽  
Yu-Rong Chen ◽  
Sheng-Yang Wang
Keyword(s):  
Major Product ◽  
Open Reading Frame ◽  
Terpene Synthase ◽  
Geranyl Diphosphate ◽  
Reading Frame ◽  
E Coli ◽  
Phylogenetic Taxonomy ◽  
Chamaecyparis Formosensis ◽  
Pcr Method

AbstractAnalyzing the gene sequences of terpene synthase (TPS) may contribute to a better understanding of terpenes biosynthesis and evolution of phylogenetic taxonomy.Chamaecyparis formosensisis an endemic and precious conifer of Taiwan. To understand the biosynthesis mechanism of terpenes in this tree, a full length of putative mono-TPS, named asCf-Pin(GeneBank accession no. EU099434), was obtained by PCR method and RACE extension. TheCf-Pinhas an 1887-bp open reading frame and encodes 628 amino acids. To identify the function ofCf-Pin,the recombinant protein fromEscherichia coliwas incubated with geranyl diphosphate, produced one major product, the structure of which was elucidated. GC/MS analysis and matching of retention time and mass spectrum with authentic standards revealed that this product isα-pinene. This is the first report of cloning of a mono-TPS and functionally expressed inE. coliand which could be identified asα-pinene synthase from a Cupressaceae conifer.

Characterization of the open reading frame 7a from Bombyx mori nucleopolyhedrovirus

2012 ◽  
Vol 40 (2) ◽  
pp. 865-873
Author(s):  
Yong Liu ◽  
Feng Yu ◽  
Huiling Wu ◽  
Qing Cao ◽  
Yu Wu ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Open Reading Frame ◽  
Bombyx Mori Nucleopolyhedrovirus ◽  
Reading Frame

Characterization of open reading frame-expressed sequence tags generated from Bos indicus and B. taurus mammary gland cDNA libraries

2004 ◽  
Vol 35 (3) ◽  
pp. 213-219 ◽  
Author(s):  
A. F. Mota ◽  
T. S. Sonstegard ◽  
C. P. Van Tassell ◽  
L. L. Shade ◽  
L. K. Matukumalli ◽  
...  
Keyword(s):  
Mammary Gland ◽  
Expressed Sequence Tags ◽  
Bos Indicus ◽  
Open Reading Frame ◽  
Cdna Libraries ◽  
Reading Frame ◽  
Expressed Sequence

scholarly journals Cloning, Nucleotide Sequence, and Expression of the Gene Encoding the Bacteriocin Boticin B from Clostridium botulinum Strain 213B

2000 ◽  
Vol 66 (12) ◽  
pp. 5480-5483 ◽  
Author(s):  
Sean S. Dineen ◽  
Marite Bradshaw ◽  
Eric A. Johnson
Keyword(s):  
Amino Acids ◽  
Nucleotide Sequence ◽  
Clostridium Botulinum ◽  
Shuttle Vector ◽  
Open Reading Frame ◽  
Gene Encoding ◽  
Reading Frame ◽  
Heat Stable ◽  
Group I

ABSTRACT Boticin B is a heat-stable bacteriocin produced byClostridium botulinum strain 213B that has inhibitory activity against various strains of C. botulinum and related clostridia. The gene encoding the bacteriocin was localized to a 3.0-kb HindIII fragment of an 18.8-kb plasmid, cloned, and sequenced. DNA sequencing revealed the boticin B structural gene,btcB, to be an open reading frame encoding 50 amino acids. A C. botulinum strain 62A transconjugant containing theHindIII fragment inserted into a clostridial shuttle vector expressed boticin B, although at much lower levels than those observed in C. botulinum 213B. To our knowledge, this is the first demonstration and characterization of a bacteriocin from toxigenic group I C. botulinum.

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