scholarly journals Oligoribonuclease Is Encoded by a Highly Conserved Gene in the 3′-5′ Exonuclease Superfamily

1998 ◽  
Vol 180 (10) ◽  
pp. 2779-2781 ◽  
Author(s):  
Xiaolan Zhang ◽  
Liuqin Zhu ◽  
Murray P. Deutscher
Keyword(s):  
Kanamycin Resistance ◽  
Open Reading Frame ◽  
Sequence Information ◽  
Gene Encoding ◽  
Reading Frame ◽  
E Coli ◽  
Kanamycin Resistance Cassette ◽  
Wide Range ◽  
Conserved Gene ◽  
Cloned Gene

ABSTRACT Oligoribonuclease, a 3′-to-5′ exoribonuclease specific for small oligoribonucleotides, was purified to homogeneity from extracts ofEscherichia coli. The purified protein is an α2 dimer of 40 kDa. NH2-terminal sequence analysis of the protein identified the gene encoding oligoribonuclease as yjeR(o204a), a previously reported open reading frame located at 94 min on the E. coli chromosome. However, as a consequence of the sequence information, the translation start site of this open reading frame has been revised. Cloning of yjeRled to overexpression of oligoribonuclease activity, and interruption of the cloned gene with a kanamycin resistance cassette eliminated the overexpression. On the basis of these data, we propose thatyjeR be renamed orn. Orthologs of oligoribonuclease are present in a wide range of organisms, extending up to humans.

Molecular and genetic analysis of the gene encoding the Saccharomyces cerevisiae strand exchange protein Sep1

1991 ◽  
Vol 11 (5) ◽  
pp. 2593-2608 ◽  
Author(s):  
D X Tishkoff ◽  
A W Johnson ◽  
R D Kolodner
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Open Reading Frame ◽  
Strand Exchange ◽  
Wild Type ◽  
Homologous Pairing ◽  
Gene Encoding ◽  
Reading Frame ◽  
Cloned Gene ◽  
Diploid Cells ◽  
Exchange Protein

Vegetatively grown Saccharomyces cerevisiae cells contain an activity that promotes a number of homologous pairing reactions. A major portion of this activity is due to strand exchange protein 1 (Sep1), which was originally purified as a 132,000-Mr species (R. Kolodner, D. H. Evans, and P. T. Morrison, Proc. Natl. Acad. Sci. USA 84:5560-5564, 1987). The gene encoding Sep1 was cloned, and analysis of the cloned gene revealed a 4,587-bp open reading frame capable of encoding a 175,000-Mr protein. The protein encoded by this open reading frame was overproduced and purified and had a relative molecular weight of approximately 160,000. The 160,000-Mr protein was at least as active in promoting homologous pairing as the original 132,000-Mr species, which has been shown to be a fragment of the intact 160,000-Mr Sep1 protein. The SEP1 gene mapped to chromosome VII within 20 kbp of RAD54. Three Tn10LUK insertion mutations in the SEP1 gene were characterized. sep1 mutants grew more slowly than wild-type cells, showed a two- to fivefold decrease in the rate of spontaneous mitotic recombination between his4 heteroalleles, and were delayed in their ability to return to growth after UV or gamma irradiation. Sporulation of sep1/sep1 diploids was defective, as indicated by both a 10- to 40-fold reduction in spore formation and reduced spore viability of approximately 50%. The majority of sep1/sep1 diploid cells arrested in meiosis after commitment to recombination but prior to the meiosis I cell division. Return-to-growth experiments showed that sep1/sep1 his4X/his4B diploids exhibited a five- to sixfold greater meiotic induction of His+ recombinants than did isogenic SEP1/SEP1 strains. sep1/sep1 mutants also showed an increased frequency of exchange between HIS4, LEU2, and MAT and a lack of positive interference between these markers compared with wild-type controls. The interaction between sep1, rad50, and spo13 mutations suggested that SEP1 acts in meiosis in a pathway that is parallel to the RAD50 pathway.

scholarly journals Molecular and genetic analysis of the gene encoding the Saccharomyces cerevisiae strand exchange protein Sep1.

1991 ◽  
Vol 11 (5) ◽  
pp. 2593-2608 ◽  
Author(s):  
D X Tishkoff ◽  
A W Johnson ◽  
R D Kolodner
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Open Reading Frame ◽  
Strand Exchange ◽  
Wild Type ◽  
Homologous Pairing ◽  
Gene Encoding ◽  
Reading Frame ◽  
Cloned Gene ◽  
Diploid Cells ◽  
Exchange Protein

Vegetatively grown Saccharomyces cerevisiae cells contain an activity that promotes a number of homologous pairing reactions. A major portion of this activity is due to strand exchange protein 1 (Sep1), which was originally purified as a 132,000-Mr species (R. Kolodner, D. H. Evans, and P. T. Morrison, Proc. Natl. Acad. Sci. USA 84:5560-5564, 1987). The gene encoding Sep1 was cloned, and analysis of the cloned gene revealed a 4,587-bp open reading frame capable of encoding a 175,000-Mr protein. The protein encoded by this open reading frame was overproduced and purified and had a relative molecular weight of approximately 160,000. The 160,000-Mr protein was at least as active in promoting homologous pairing as the original 132,000-Mr species, which has been shown to be a fragment of the intact 160,000-Mr Sep1 protein. The SEP1 gene mapped to chromosome VII within 20 kbp of RAD54. Three Tn10LUK insertion mutations in the SEP1 gene were characterized. sep1 mutants grew more slowly than wild-type cells, showed a two- to fivefold decrease in the rate of spontaneous mitotic recombination between his4 heteroalleles, and were delayed in their ability to return to growth after UV or gamma irradiation. Sporulation of sep1/sep1 diploids was defective, as indicated by both a 10- to 40-fold reduction in spore formation and reduced spore viability of approximately 50%. The majority of sep1/sep1 diploid cells arrested in meiosis after commitment to recombination but prior to the meiosis I cell division. Return-to-growth experiments showed that sep1/sep1 his4X/his4B diploids exhibited a five- to sixfold greater meiotic induction of His+ recombinants than did isogenic SEP1/SEP1 strains. sep1/sep1 mutants also showed an increased frequency of exchange between HIS4, LEU2, and MAT and a lack of positive interference between these markers compared with wild-type controls. The interaction between sep1, rad50, and spo13 mutations suggested that SEP1 acts in meiosis in a pathway that is parallel to the RAD50 pathway.

scholarly journals d-Xylose (d-glucose) isomerase from Arthrobacter strain N.R.R.L. B3728. Gene cloning, sequence and expression

1991 ◽  
Vol 277 (1) ◽  
pp. 263-271 ◽  
Author(s):  
T Loviny-Anderton ◽  
P C Shaw ◽  
M K Shin ◽  
B S Hartley
Keyword(s):  
Sequence Similarity ◽  
Shuttle Vector ◽  
Xylose Isomerase ◽  
Glucose Isomerase ◽  
Open Reading Frame ◽  
Reading Frame ◽  
E Coli ◽  
Ribosome Binding ◽  
Arthrobacter Strain ◽  
Cloned Gene

Arthrobacter strain N.R.R.L. B3728 superproduces a D-xylose isomerase that is also a useful industrial D-glucose isomerase. The gene (xylA) that encodes it has been cloned by complementing a xylA mutant of the ancestral strain, with the use of a shuttle vector. The 5′ region shows strong sequence similarity to Escherichia coli consensus promoters and ribosome-binding sequences and allows high levels of expression in E. coli. The coding sequence shows similarity to those for other D-xylose isomerases and is followed by 22 nucleotide residues with stop codons in each reading frame, a good ‘consensus’ ribosome-binding site and an open reading frame showing similarity to those of known D-xylulokinases (xylB). Studies on the expression of the cloned gene in Arthrobacter and in E. coli suggest that the two genes are part of a xyl operon regulated by a repressor that is defective in strain B3728. Codon usage in these two genes, and in another open reading frame (nxi) that was adventitiously isolated during early cloning attempts, shows some characteristic omissions and a strong G + C preference in redundant positions.

scholarly journals OxyR Acts as a Repressor of Catalase Expression in Neisseria gonorrhoeae

2003 ◽  
Vol 71 (1) ◽  
pp. 550-556 ◽  
Author(s):  
Hsing-Ju Tseng ◽  
Alastair G. McEwan ◽  
Michael A. Apicella ◽  
Michael P. Jennings
Keyword(s):  
Hydrogen Peroxide ◽  
Neisseria Gonorrhoeae ◽  
Catalase Activity ◽  
Kanamycin Resistance ◽  
Gene Encoding ◽  
E Coli ◽  
Kanamycin Resistance Cassette ◽  
Serovar Typhimurium ◽  
High Level ◽  
And Function

ABSTRACT It has been reported that Neisseria gonorrhoeae possesses a very high level of catalase activity, but the regulation of catalase expression has not been investigated extensively. In Escherichia coli and Salmonella enterica serovar Typhimurium, it has been demonstrated that OxyR is a positive regulator of hydrogen peroxide-inducible genes, including the gene encoding catalase. The oxyR gene from N. gonorrhoeae was cloned and used to complement an E. coli oxyR mutant, confirming its identity and function. The gene was inactivated by inserting a kanamycin resistance cassette and used to make a knockout allele on the chromosome of N. gonorrhoeae strain 1291. In contrast to E. coli, the N. gonorrhoeae oxyR::kan mutant expressed ninefold-more catalase activity and was more resistant to hydrogen peroxide killing than the wild type. These data are consistent with OxyR in N. gonorrhoeae acting as a repressor of catalase expression.

scholarly journals YfcX Enables Medium-Chain-Length Poly(3-Hydroxyalkanoate) Formation from Fatty Acids in Recombinant Escherichia coli fadB Strains

2002 ◽  
Vol 184 (20) ◽  
pp. 5696-5705 ◽  
Author(s):  
Kristi D. Snell ◽  
Feng Feng ◽  
Luhua Zhong ◽  
David Martin ◽  
Lara L. Madison
Keyword(s):  
Escherichia Coli ◽  
Fatty Acids ◽  
Chain Length ◽  
Open Reading Frame ◽  
Gene Encoding ◽  
Reading Frame ◽  
E Coli ◽  
Medium Chain ◽  
Medium Chain Length ◽  
Insertional Inactivation

ABSTRACT Expression of Escherichia coli open reading frame yfcX is shown to be required for medium-chain-length polyhydroxyalkanoate (PHAMCL) formation from fatty acids in an E. coli fadB mutant. The open reading frame encodes a protein, YfcX, with significant similarity to the large subunit of multifunctional β-oxidation enzymes. E. coli fadB strains modified to contain an inactivated copy of yfcX and to express a medium-chain-length synthase are unable to form PHAMCLs when grown in the presence of fatty acids. Plasmid-based expression of yfcX in the FadB− YfcX− PhaC+ strain restores polymer formation. YfcX is shown to be a multifunctional enzyme that minimally encodes hydratase and dehydrogenase activities. The gene encoding YfcX is located downstream from yfcY, a gene encoding thiolase activity. Results of insertional inactivation studies and enzyme activity analyses suggest a role for yfcX in PHA monomer unit formation in recombinant E. coli fadB mutant strains. Further studies are required to determine the natural role of YfcX in the metabolism of E. coli.

scholarly journals The Archaeoglobus fulgidusd-Lactate Dehydrogenase Is a Zn2+Flavoprotein

1999 ◽  
Vol 181 (24) ◽  
pp. 7580-7587 ◽  
Author(s):  
David W. Reed ◽  
Patricia L. Hartzell
Keyword(s):  
Lactate Dehydrogenase ◽  
Fusion Protein ◽  
Factor Xa ◽  
Sole Source ◽  
Open Reading Frame ◽  
Archaeoglobus Fulgidus ◽  
Sulfate Reducer ◽  
Gene Encoding ◽  
Reading Frame ◽  
E Coli

ABSTRACT Archaeoglobus fulgidus, a hyperthermophilic, archaeal sulfate reducer, is one of the few organisms that can utilized-lactate as a sole source for both carbon and electrons. The A. fulgidus open reading frame, AF0394, which is predicted to encode a d-(−)-lactate dehydrogenase (Dld), was cloned, and its product was expressed in Escherichia coli as a fusion with the maltose binding protein (MBP). The 90-kDa MBP-Dld fusion protein was more efficiently expressed inE. coli when coexpressed with the E. coli dnaYgene, encoding the arginyl tRNA for the codons AGA and AGG. When cleaved from the fusion protein by treatment with factor Xa, the recombinant Dld (rDld) has an apparent molecular mass of 50 kDa, similar to that of the native A. fulgidus Dld enzyme. Both the purified MBP-Dld fusion protein and its rDld cleavage fragment have lactate dehydrogenase activities specific for d-lactate, are stable at 80°C, and retain activity after exposure to oxygen. The flavin cofactor FAD, which binds rDld apoprotein with a 1:1 stoichiometry, is essential for activity.

scholarly journals GIT1, a Gene Encoding a Novel Transporter for Glycerophosphoinositol in Saccharomyces cerevisiae

Genetics ◽  
1998 ◽  
Vol 149 (4) ◽  
pp. 1707-1715 ◽  
Author(s):  
J L Patton-Vogt ◽  
S A Henry
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Regulatory Gene ◽  
Sugar Transport ◽  
Open Reading Frame ◽  
Gene Encoding ◽  
Reading Frame ◽  
Membrane Spanning ◽  
Membrane Spanning Domains ◽  
Uptake And Metabolism ◽  
Cells Cultured

Abstract Phosphatidylinositol catabolism in Saccharomyces cerevisiae cells cultured in media containing inositol results in the release of glycerophosphoinositol (GroPIns) into the medium. As the extracellular concentration of inositol decreases with growth, the released GroPIns is transported back into the cell. Exploiting the ability of the inositol auxotroph, ino1, to use exogenous GroPIns as an inositol source, we have isolated mutants (Git−) defective in the uptake and metabolism of GroPIns. One mutant was found to be affected in the gene encoding the transcription factor, SPT7. Mutants of the positive regulatory gene INO2, but not of its partner, INO4, also have the Git− phenotype. Another mutant was complemented by a single open reading frame (ORF) termed GIT1 (glycerophosphoinositol). This ORF consists of 1556 bp predicted to encode a polypeptide of 518 amino acids and 57.3 kD. The predicted Git1p has similarity to a variety of S. cerevisiae transporters, including a phosphate transporter (Pho84p), and both inositol transporters (Itr1p and Itr2p). Furthermore, Git1p contains a sugar transport motif and 12 potential membrane-spanning domains. Transport assays performed on a git1 mutant together with the above evidence indicate that the GIT1 gene encodes a permease involved in the uptake of GroPIns.

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 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.

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