scholarly journals A lipoxygenase with linoleate diol synthase activity from Nostoc sp. PCC 7120

2008 ◽  
Vol 410 (2) ◽  
pp. 347-357 ◽  
Author(s):  
Imke Lang ◽  
Cornelia Göbel ◽  
Andrea Porzel ◽  
Ingo Heilmann ◽  
Ivo Feussner
Keyword(s):  
Main Product ◽  
Genomic Sequence ◽  
Octadecadienoic Acid ◽  
Lipid Peroxide ◽  
Full Length ◽  
Ph Optimum ◽  
Reading Frame ◽  
Diol Synthase ◽  
Pcc 7120 ◽  
Lox Products

The dioxygenation of PUFAs (polyunsaturated fatty acids) in plants is mainly catalysed by members of the LOX (lipoxygenase) enzyme family. LOX products may be further metabolized, and are known as signalling substances in plant development and in responses to wounding and pathogen attack. In contrast with the situation in eukaryotes, information on the relevance of lipid peroxide metabolism in prokaryotic organisms is scarce. Therefore, we aimed to analyse LOXs and oxylipin patterns of cyanobacterial origin. A search of the genomic sequence of the cyanobacterium Nostoc sp. PCC 7120 suggested an open reading frame encoding a putative LOX named NspLOX that harboured an N-terminal extension. Individual analysis of recombinant C-terminal domain revealed enzymatic activity as a linoleate (9R)-LOX. Analysis of the full-length NspLOX protein, however, revealed linoleate diol synthase activity, generating (10E,12E)-9,14-dihydroxy-10,12-octadecadienoic acid as the main product from LA (linoleic acid) and (10E,12E,14E)-9,16-dihydroxy-10,12,14-octadecatrienoic acid as the main product from ALA (α-LA) substrates respectively, with ALA as preferred substrate. The enzyme exhibited a broad pH optimum between pH 7 and pH 10. Soluble extracts of Nostoc sp. contain more 9-LOX-derived hydroperoxides in sonified than in non-sonified cells, but products of full-length NspLOX were not detectable under the conditions used. As no other LOX-like sequence was identified in the genome of Nostoc sp. PCC 7120, the results presented suggest that (9R)-LOX-derived oxylipins may represent the endogenous products of NspLOX. Based on the biochemical results of NspLOX, we suggest that this bifunctional enzyme may represent a more ancient way to control the intracellular amount of oxylipins in this cyanobacterium.

scholarly journals Regulation of an Osmoticum-Responsive Gene in Anabaena sp. Strain PCC 7120

1998 ◽  
Vol 180 (23) ◽  
pp. 6332-6337 ◽  
Author(s):  
Steven H. Schwartz ◽  
Todd A. Black ◽  
Karin Jäger ◽  
Jean-Michel Panoff ◽  
C. Peter Wolk
Keyword(s):  
Genomic Sequence ◽  
Response Regulator ◽  
Sequence Similarity ◽  
Open Reading Frame ◽  
Response Regulators ◽  
Reading Frame ◽  
Regulatory Systems ◽  
Entire Open Reading Frame ◽  
Anabaena Sp ◽  
Pcc 7120

ABSTRACT Salt-induced genes in the cyanobacterium Anabaena sp. strain PCC 7120 were identified by use of a Tn5-based transposon bearing luxAB as a reporter. The genomic sequence adjacent to one site of insertion of the transposon was identical in part to the sequence of thelti2 gene, which was previously identified in a differential screen for cold-induced transcripts in Anabaena variabilis. The lti2-like gene was induced by sucrose and other osmotica and by low temperature, in addition to salt. Regulatory components necessary for the induction of this gene by osmotica were sought by a further round of transposon mutagenesis. One mutant that displayed reduced transcriptional activity of thelti2-like gene in response to exposure to osmotica had an insertion in an open reading frame, which was denoted orrA, whose predicted product showed sequence similarity to response regulators from two-component regulatory systems. The corresponding mutation was reconstructed and was shown, like the second-site transposon mutation, to result in reduced response to osmotic stress. Induction of the lux reporter gene by osmotica was restored by complementation with a genomic fragment containing the entire open reading frame for the presumptive response regulator, whereas a fragment containing a truncated copy of the open reading frame for the response regulator did not complement the mutation.

scholarly journals patS Minigenes Inhibit Heterocyst Development of Anabaena sp. Strain PCC 7120

2004 ◽  
Vol 186 (19) ◽  
pp. 6422-6429 ◽  
Author(s):  
Xiaoqiang Wu ◽  
Duan Liu ◽  
Martin H. Lee ◽  
James W. Golden
Keyword(s):  
Fluorescent Protein ◽  
Full Length ◽  
Published Data ◽  
Developmentally Regulated ◽  
Reading Frame ◽  
Type Pattern ◽  
Anabaena Sp ◽  
Green Fluorescent ◽  
Pcc 7120 ◽  
Heterocyst Development

ABSTRACT The patS gene encodes a small peptide that is required for normal heterocyst pattern formation in the cyanobacterium Anabaena sp. strain PCC 7120. PatS is proposed to control the heterocyst pattern by lateral inhibition. patS minigenes were constructed and expressed by different developmentally regulated promoters to gain further insight into PatS signaling. patS minigenes patS4 to patS8 encode PatS C-terminal 4 (GSGR) to 8 (CDERGSGR) oligopeptides. When expressed by P petE , P patS , or P rbcL promoters, patS5 to patS8 inhibited heterocyst formation but patS4 did not. In contrast to the full-length patS gene, P hepA-patS5 failed to restore a wild-type pattern in a patS null mutant, indicating that PatS-5 cannot function in cell-to-cell signaling if it is expressed in proheterocysts. To establish the location of the PatS receptor, PatS-5 was confined within the cytoplasm as a gfp-patS5 fusion. The green fluorescent protein GFP-PatS-5 fusion protein inhibited heterocyst formation. Similarly, full-length PatS with a C-terminal hexahistidine tag inhibited heterocyst formation. These data indicate that the PatS receptor is located in the cytoplasm, which is consistent with recently published data indicating that HetR is a PatS target. We speculated that overexpression of other Anabaena strain PCC 7120 RGSGR-encoding genes might show heterocyst inhibition activity. In addition to patS and hetN, open reading frame (ORF) all3290 and an unannotated ORF, orf77, encode an RGSGR motif. Overexpression of all3290 and orf77 under the control of the petE promoter inhibited heterocyst formation, indicating that the RGSGR motif can inhibit heterocyst development in a variety of contexts.

scholarly journals Analysis and phylogenetic comparisons of full-length VP2 genes of the 24 bluetongue virus serotypes

2007 ◽  
Vol 88 (2) ◽  
pp. 621-630 ◽  
Author(s):  
S. Maan ◽  
N. S. Maan ◽  
A. R. Samuel ◽  
S. Rao ◽  
H. Attoui ◽  
...  
Keyword(s):  
Bluetongue Virus ◽  
Neutralizing Antibodies ◽  
Neutralizing Antibody ◽  
Full Length ◽  
Molecular Diagnostic ◽  
Mammalian Host ◽  
Reading Frame ◽  
Diagnostic Assays ◽  
Primary Determinant ◽  
Serotype Identification

The outer capsid protein VP2 of Bluetongue virus (BTV) is a target for the protective immune response generated by the mammalian host. VP2 contains the majority of epitopes that are recognized by neutralizing antibodies and is therefore also the primary determinant of BTV serotype. Full-length cDNA copies of genome segment 2 (Seg-2, which encodes VP2) from the reference strains of each of the 24 BTV serotypes were synthesized, cloned and sequenced. This represents the first complete set of full-length BTV VP2 genes (from the 24 serotypes) that has been analysed. Each Seg-2 has a single open reading frame, with short inverted repeats adjacent to conserved terminal hexanucleotide sequences. These data demonstrated overall inter-serotype variations in Seg-2 of 29 % (BTV-8 and BTV-18) to 59 % (BTV-16 and BTV-22), while the deduced amino acid sequence of VP2 varied from 22.4 % (BTV-4 and BTV-20) to 73 % (BTV-6 and BTV-22). Ten distinct Seg-2 lineages (nucleotypes) were detected, with greatest sequence similarities between those serotypes that had previously been reported as serologically ‘related’. Fewer similarities were observed between different serotypes in regions of VP2 that have been reported as antigenically important, suggesting that they may play a role in the neutralizing antibody response. The data presented form an initial basis for BTV serotype identification by sequence analyses and comparison of Seg-2, and for development of molecular diagnostic assays for individual BTV serotypes (by RT-PCR).

First full-length genomic sequence of a hepatitis A virus isolated in Argentina shows recombination between subgenotypes IA and IB

2011 ◽  
Vol 155 (1) ◽  
pp. 316-324 ◽  
Author(s):  
Sebastian Aguirre ◽  
Viviana Malirat ◽  
Eduardo Scodeller ◽  
Nora Mattion
Keyword(s):  
Hepatitis A ◽  
Genomic Sequence ◽  
Hepatitis A Virus ◽  
Full Length

scholarly journals Expression of Functional CD32 Molecules on Human NK Cells Is Determined by an Allelic Polymorphism of the FcγRIIC Gene

Blood ◽  
1998 ◽  
Vol 91 (7) ◽  
pp. 2369-2380 ◽  
Author(s):  
Diana Metes ◽  
Linda K. Ernst ◽  
William H. Chambers ◽  
Andrei Sulica ◽  
Ronald B. Herberman ◽  
...  
Keyword(s):  
Nk Cells ◽  
Null Allele ◽  
Nk Cell ◽  
Full Length ◽  
Null Alleles ◽  
Soluble Form ◽  
Allelic Polymorphism ◽  
Reading Frame ◽  
Normal Individuals ◽  
Alternatively Spliced

Human natural killer (NK) cells were thought to express only FcγRIIIA (CD16), but recent reports have indicated that NK cells also express a second type of FcγR, ie, FcγRII (CD32). We have isolated, cloned, and sequenced full-length cDNAs of FcγRII from NK cells derived from several normal individuals that may represent four different products of the FcγRIIC gene. One transcript (IIc1) is identical with the already described FcγRIIc form. The other three (IIc2-IIc4) appear to represent unique, alternatively spliced products of the same gene, and include a possible soluble form. Analyses of the full-length clones have revealed an allelic polymorphism in the first extracellular exon, resulting in either a functional open reading frame isoform or a null allele. Stable transfection experiments enabled us to determine a unique binding pattern of anti-CD32 monoclonal antibodies to FcγRIIc. Further analyses of NK-cell preparations revealed heterogeneity in CD32 expression, ranging from donors lacking CD32 expression to donors expressing high levels of CD32 that were capable of triggering cytotoxicity. Differences in expression were correlated with the presence or absence of null alleles. These data show that certain individuals express high levels of functional FcγRIIc isoforms on their NK cells.

scholarly journals The Two Drosophila Telomeric Transposable Elements Have Very Different Patterns of Transcription

1999 ◽  
Vol 19 (1) ◽  
pp. 873-881 ◽  
Author(s):  
O. N. Danilevskaya ◽  
K. L. Traverse ◽  
N. C. Hogan ◽  
P. G. DeBaryshe ◽  
M. L. Pardue
Keyword(s):  
Transposable Elements ◽  
Sequence Similarity ◽  
Sequence Divergence ◽  
Full Length ◽  
Coding Region ◽  
Free Standing ◽  
Reading Frame ◽  
Sequence Organization ◽  
Sense Strand ◽  
Cell Fractions

ABSTRACT The transposable elements HeT-A and TARTconstitute the telomeres of Drosophila chromosomes. Both are non-long terminal repeat (LTR) retrotransposons, sharing the remarkable property of transposing only to chromosome ends. In addition, strong sequence similarity of their gag proteins indicates that these coding regions share a common ancestor. These findings led to the assumption that HeT-A andTART are closely related. However, we now find that these elements produce quite different sets of transcripts. HeT-Aproduces only sense-strand transcripts of the full-length element, whereas TART produces both sense and antisense full-length RNAs, with antisense transcripts in more than 10-fold excess over sense RNA. In addition, features of TART sequence organization resemble those of a subclass of non-LTR elements characterized by unequal terminal repeats. Thus, the ancestral gag sequence appears to have become incorporated in two different types of elements, possibly with different functions in the telomere. HeT-Atranscripts are found in both nuclear and cytoplasmic cell fractions, consistent with roles as both mRNA and transposition template. In contrast, both sense and antisense TART transcripts are almost entirely concentrated in nuclear fractions. Also,TART open reading frame 2 probes detect a cytoplasmic mRNA for reverse transcriptase (RT), with no similarity to TARTsequence 5′ or 3′ of the RT coding region. This RNA could be a processed TART transcript or the product of a “free-standing” RT gene. Either origin would be novel. The distinctive transcription patterns of both HeT-A andTART are conserved in Drosophila yakuba, despite significant sequence divergence. The conservation argues that these sets of transcripts are important to the function(s) ofHeT-A and TART.

scholarly journals Full-Length Genomic Sequence of Subgenotype IIIA Hepatitis A Virus Isolate in Republic of Korea

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Ah-Ra Lee ◽  
Sung-Geun Lee ◽  
Lae-Hyung Kang ◽  
Weon-Hwa Jheong ◽  
Soon-Young Paik
Keyword(s):  
Amino Acid ◽  
Hepatitis A ◽  
Genomic Sequence ◽  
Hepatitis A Virus ◽  
Full Length ◽  
Republic Of Korea ◽  
Nucleotide Sequencing ◽  
Number Of Patients ◽  
The Republic ◽  
Alignment Analysis

Hepatitis A virus is known to cause acute hepatitis and has significant implications for public health throughout the world. In the Republic of Korea, the number of patients with hepatitis A virus infection has been increasing rapidly since 2006. In this study, the Kor-HAV-F strain was identified as subgenotype IIIA by RT-PCR, and its identity was confirmed by nucleotide sequencing and alignment analysis. Moreover, detailed phylogenetic analysis indicated that the Kor-HAV-F strain clustered into subgenotype IIIA, including strains isolated in Japan, Norway, and India. The entire amino acid sequence of the VP1 and 2A regions was compared with that of the reference strains isolated in various countries. We found 2 amino acid changes (T168A and L96P, resp.) in the VP1 and 2A regions, which had not been found in any other hepatitis A virus strain. To our knowledge, this study is the first to report the full-length sequence of a hepatitis A virus isolated in the Republic of Korea.

scholarly journals Production of In Vitro Lytic Characteristics of Paroxysmal Nocturnal Hemoglobinuria Erythrocytes in Normal Erythrocytes

Blood ◽  
1968 ◽  
Vol 32 (1) ◽  
pp. 49-58 ◽  
Author(s):  
HERBERT E. KANN ◽  
CHARLES E. MENGEL ◽  
WILHELM D. MERIWETHER ◽  
LARRY EBBERT
Keyword(s):  
Disulfide Bonds ◽  
Reduced Glutathione ◽  
Lipid Peroxide ◽  
Acetylcholinesterase Activity ◽  
Membrane Lipid ◽  
Alkaline Solutions ◽  
Magnesium Ion ◽  
Ph Optimum ◽  
Protein Disulfide Bonds

Abstract The concept that production of a "perfect" PNH RBC, artificially, might supply information as to the nature of the defect(s) in PNH RBCs was the basis for a study in which normal RBCs were studied after preincubation in concentrated, alkaline solutions of reduced glutathione. These RBCs exhibited the following features of PNH RBCs. 1. Sensitivity to lysis by acidified serum a. pH optimum identical to that of PNH RBCs b. complete prevention by prior heating of serum to 56° C for 30 minutes c. complete prevention by addition of dextran to serum d. complete prevention by removal of magnesium ion from serum, reversed by re-addition of magnesium ion to serum 2. Positive thrombin lysis test. 3. Positive sucrose lysis test. 4. No agglutination in type-compatible serum. 5. No greater than normal agglutination in serum containing isoantibodies or elevated titers of cold agglutinins, but marked enhancement of lytic sensitivity to these antibodies, identical to that achieved with "natural" PNH cells. 6. Positive Hegglin-Maier test. 7. Decreased acetylcholinesterase activity. 8. Increased lysis and lipid peroxide formation during incubation with hydrogen peroxide. The broad scope of these similarities permits cautious speculation that some biochemical feature(s) of PNH RBCs may have been produced in normal RBCs, artificially. The mechanism by which reduced glutathione produces the change is uncertain, but may involve either oxidation of membrane lipid or splitting of membrane protein disulfide bonds, or both.

Cloning and characterisation of the gene encoding HMG-CoA reductase from Taxus media and its functional identification in yeast

2004 ◽  
Vol 31 (1) ◽  
pp. 73 ◽  
Author(s):  
Zhihua Liao ◽  
Qiumin Tan ◽  
Yourong Chai ◽  
Kaijing Zuo ◽  
Min Chen ◽  
...  
Keyword(s):  
Blot Analysis ◽  
Catalytic Domain ◽  
Bioinformatic Analysis ◽  
Full Length ◽  
Functional Identification ◽  
Reading Frame ◽  
Full Length Cdna ◽  
Taxus Media ◽  
Taxol Biosynthesis ◽  
Coa Reductase

In plants, the first committed step in the pathway for biosynthesis of isoprenoids is catalysed by 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR, EC: 1.1.1.34). Here we report for the first time the cloning of a full-length cDNA encoding HMGR (Tm–HMGR) from a taxol-producing gymnosperm, Taxus media Rehder. The full-length cDNA of Tm–HMGR (GenBank accession number: AY277740) was 2307 base pairs (bp), with a 1791-bp open reading frame (ORF) encoding a 596-amino-acid polypeptide. Bioinformatic analysis revealed that Tm–HMGR contained two trans-membrane domains and a catalytic domain, and showed high homology to other plant HMGRs. Phylogenetic analysis indicated that Tm–HMGR was more ancient than other plant HMGRs. The structural modelling showed that Tm–HMGR had the typical spatial structure of HMGRs whose catalytic domains could be folded and divided into three spatial domains, L-domain, N-domain and S-domain. Southern blot analysis revealed that Tm–HMGR belonged to a small HMGR gene family. Northern blot analysis showed that Tm–HMGR was expressed in roots, stems and needles, with higher expression in stems and needles than in roots. Functional complementation of Tm–HMGR in a HMGR-deficient mutant yeast demonstrated that Tm–HMGR mediated the biosynthesis of mevalonate and provided the general precursor for taxol biosynthesis.

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