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Score: 17.00 | Title: Differential Accumulation of Salicylic Acid and Salicylic Acid-Sensitive Catalase in Different Rice it issues .
| Author: Chen Z Iyer S Caplan A Klessig DF Fan B | Journal: Citation: V : 114 ( 1 ) P : 193-201 Year: 1997 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub12223699 Accession (PMID): 12223699 | Abstract: We previously proposed that salicylic acid ( SA ) -sensitive catalases serve as biological targets of SA in plant defense responses .
To further examine the role of SA-sensitive catalases , we have analyzed the relationship between SA levels and SA sensitivity of catalases in different rice ( Oryza sativa ) it issues .
We show here that , whereas rice shoots contain extremely high levels of free SA , as previously reported ( I Raskin , H Skubatz , W Tang , BJD Meeuse [ 1990 ] Ann Bot 66 : 369-373 ; P Silverman , M Seskar , D Kanter , P Schweizer , J-P Metraux , I Raskin [ 1995 ] Plant Physiol 108 : 633-639 ) , rice roots and cell-suspension cultures have very low SA levels .
Catalases from different rice it issues also exhibit differences in sensitivity to SA .
Catalase from rice shoots is insensitive to SA , but roots and cell-suspension cultures contain SA-sensitive catalase .
The difference in SA sensitivity of catalases from these different it issues correlates with the it issue-specific expression of two catalase genes , CatA and CatB , which encode highly distinctive catalase proteins .
CatA , which encodes a catalase with relatively low sequence homology to the tobacco SA-sensitive catalases , is expressed at high levels exclusively in the shoots .
On the other hand , in roots and cell-suspension cultures , with northern analysis we detected expression of only the CatB gene , which encodes a catalase with higher sequence homology to tobacco catalases .
The role of catalases in mediating some of the SA-induced responses is discussed in light of these results and the recently defined mechanisms of catalase inhibition by SA . | Matching Sentences: [ Sen. 6, subscore: 4.00 ]: The difference in SA sensitivity of catalases from these different it issues correlates with the it issue-specific expression of two catalase genes , CatA and CatB , which encode highly distinctive catalase proteins . [ Sen. 7, subscore: 3.00 ]: CatA , which encodes a catalase with relatively low sequence homology to the tobacco SA-sensitive catalases , is expressed at high levels exclusively in the shoots . [ Sen. 2, subscore: 2.00 ]: To further examine the role of SA-sensitive catalases , we have analyzed the relationship between SA levels and SA sensitivity of catalases in different rice ( Oryza sativa ) it issues . [ Sen. 5, subscore: 2.00 ]: Catalase from rice shoots is insensitive to SA , but roots and cell-suspension cultures contain SA-sensitive catalase . [ Sen. 8, subscore: 2.00 ]: On the other hand , in roots and cell-suspension cultures , with northern analysis we detected expression of only the CatB gene , which encodes a catalase with higher sequence homology to tobacco catalases . [ Sen. 9, subscore: 2.00 ]: The role of catalases in mediating some of the SA-induced responses is discussed in light of these results and the recently defined mechanisms of catalase inhibition by SA . [ Sen. 1, subscore: 1.00 ]: We previously proposed that salicylic acid ( SA ) -sensitive catalases serve as biological targets of SA in plant defense responses . [ Sen. 4, subscore: 1.00 ]: Catalases from different rice it issues also exhibit differences in sensitivity to SA .
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Score: 16.00 | Title: Molecular evolution of maize catalases and their relationship to other eukaryotic and prokaryotic catalases .
| Author: Guan L Scandalios JG .
| Journal: J Mol .
Evol Citation: V : 42 ( 5 ) P : 570-9 Year: 1996 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub8662009 Accession (PMID): 8662009 | Abstract: We have compared the nucleotide and protein sequences of the three maize catalase genes with other plant catalases to reconstruct the evolutionary relationship among these catalases .
These sequences were also compared with other eukaryotic and prokaryotic catalases .
Phylogenies based on distances and parsimony analysis show that all plant catalases derive from a common ancestral catalase gene and can be divided into three distinct groups .
The first , and major , group includes maize Cat1 , barley Cat1 , rice CatB , and most of the dicot catalases .
The second group is an apparent dicot-specific catalase group encompassing the tobacco Cat2 and tomato Cat .
The third is a monocot-specific catalase class including the maize Cat3 , barley Cat2 , and rice CatA .
The maize Cat2 gene is loosely related to the first group .
The distinctive features of monocot-specific catalases are their extreme high codon bias at the third position and low degree of sequence similarity to other plant catalases .
Similarities in the intron positions for several plant catalase genes support the conclusion of derivation from a common ancestral gene .
The similar intron position between bean catalases and human catalase implies that the animal and plant catalases might have derived from a common progenitor gene sequence .
| Matching Sentences: [ Sen. 1, subscore: 3.00 ]: We have compared the nucleotide and protein sequences of the three maize catalase genes with other plant catalases to reconstruct the evolutionary relationship among these catalases . [ Sen. 10, subscore: 3.00 ]: The similar intron position between bean catalases and human catalase implies that the animal and plant catalases might have derived from a common progenitor gene sequence . [ Sen. 3, subscore: 2.00 ]: Phylogenies based on distances and parsimony analysis show that all plant catalases derive from a common ancestral catalase gene and can be divided into three distinct groups . [ Sen. 6, subscore: 2.00 ]: The third is a monocot-specific catalase class including the maize Cat3 , barley Cat2 , and rice CatA . [ Sen. 8, subscore: 2.00 ]: The distinctive features of monocot-specific catalases are their extreme high codon bias at the third position and low degree of sequence similarity to other plant catalases . [ Sen. 2, subscore: 1.00 ]: These sequences were also compared with other eukaryotic and prokaryotic catalases . [ Sen. 4, subscore: 1.00 ]: The first , and major , group includes maize Cat1 , barley Cat1 , rice CatB , and most of the dicot catalases . [ Sen. 5, subscore: 1.00 ]: The second group is an apparent dicot-specific catalase group encompassing the tobacco Cat2 and tomato Cat . [ Sen. 9, subscore: 1.00 ]: Similarities in the intron positions for several plant catalase genes support the conclusion of derivation from a common ancestral gene .
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Score: 12.00 | Title: Catalytic pyrolysis of waste rice husk over mesoporous materials .
| Author: Jeon MJ Kim SS Jeon JK Park SH Kim JM Sohn JM Lee SH Park YK | Journal: Nanoscale Res Lett Citation: V : 7 P : 18 Year: 2012 Type: Publisher | Literature: oryza Field: abstract Doc ID: pub22221540 Accession (PMID): 22221540 | Abstract: ABSTRACT : Catalytic fast pyrolysis of waste rice husk was carried out using pyrolysis-gas chromatography/mass spectrometry [ Py-GC/MS ] .
Meso-MFI zeolite [ Meso-MFI ] was used as the catalyst In addition , a 0 . 5-wt . % platinum [ Pt ] was ion-exchanged into Meso-MFI to examine the effect of Pt addition .
Using a catalytic upgrading method , the activities of the catalysts were evaluated in terms of product composition and deoxygenation .
The structure and acid site characteristics of the catalysts were analyzed by Brunauer-Emmett-Teller surface area measurement and NH3 temperature-programmed desorption analysis .
Catalytic upgrading reduced the amount of oxygenates in the product vapor due to the cracking reaction of the catalysts .
Levoglucosan , a polymeric oxygenate species , was completely decomposed without being detected .
While the amount of heavy phenols was reduced by catalytic upgrading , the amount of light phenols was increased because of the catalytic cracking of heavy phenols into light phenols and aromatics .
The amount of aromatics increased remarkably as a result of catalytic upgrading , which is attributed to the strong Bronsted acid sites and the shape selectivity of the Meso-MFI catalyst The addition of Pt made the Meso-MFI catalyst even more active in deoxygenation and in the production of aromatics .
| Matching Sentences: [ Sen. 8, subscore: 3.00 ]: The amount of aromatics increased remarkably as a result of catalytic upgrading , which is attributed to the strong Bronsted acid sites and the shape selectivity of the Meso-MFI catalyst The addition of Pt made the Meso-MFI catalyst even more active in deoxygenation and in the production of aromatics . [ Sen. 3, subscore: 2.00 ]: Using a catalytic upgrading method , the activities of the catalysts were evaluated in terms of product composition and deoxygenation . [ Sen. 5, subscore: 2.00 ]: Catalytic upgrading reduced the amount of oxygenates in the product vapor due to the cracking reaction of the catalysts . [ Sen. 7, subscore: 2.00 ]: While the amount of heavy phenols was reduced by catalytic upgrading , the amount of light phenols was increased because of the catalytic cracking of heavy phenols into light phenols and aromatics . [ Sen. 1, subscore: 1.00 ]: ABSTRACT : Catalytic fast pyrolysis of waste rice husk was carried out using pyrolysis-gas chromatography/mass spectrometry [ Py-GC/MS ] . [ Sen. 2, subscore: 1.00 ]: Meso-MFI zeolite [ Meso-MFI ] was used as the catalyst In addition , a 0 . 5-wt . % platinum [ Pt ] was ion-exchanged into Meso-MFI to examine the effect of Pt addition . [ Sen. 4, subscore: 1.00 ]: The structure and acid site characteristics of the catalysts were analyzed by Brunauer-Emmett-Teller surface area measurement and NH3 temperature-programmed desorption analysis .
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Score: 11.00 | Title: A rural population based case-control study of senile cataract in India .
| Author: Sreenivas V Prabhakar AK Badrinath SS Fernandez T Roy IS Sharma T Shah B | Journal: Citation: V : 9 ( 5 ) P : 327-36 Year: 1999 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub10616266 Accession (PMID): 10616266 | Abstract: PURPOSE : Senile cataract contributes to 75% of blindness in India and there is a growing backlog of cataract cases needing surgery .
The present study seeks clues to the etiology of senile cataract , so that strategies to prevent or even delay cataract formation could be planned .
METHODS : Using a community based case-control design , 258 cases & 308 controls from one centre and 301 cases & 591 controls from another were studied .
The subjects were from rural areas and were aged 40-60 years .
Logistic regression analysis technique was employed to study the associations between senile cataract and various variables .
RESULTS : Systolic blood pressure , duration of exposure to sunlight per day were associated with senile cataract in both the centres ( OR = 1 . 4 & 1 . 5 for systolic BP and 1 . 6 & 1 . 4 for exposure to sunlight ) .
Utilization of rice gruel ( OR = 0 . 5 ) , duration of exposure to fire & dust per day ( OR = 1 . 8 ) , family history of cataract ( OR = 5 . 0 ) , use of cheap cooking fuels ( OR = 1 . 8 ) , increased height ( OR = 0 . 7 ) and increased number of hours of work per day ( OR = 0 . 7 ) were other variables that showed significant association in either of the centres .
CONCLUSION : Senile cataract appears to have a multi factorial etiology .
Though the study provided some clues to the etiology of senile cataract , further studies are needed to know the specific role of these factors in the causation of cataract , so that any preventive or control measures could be initiated in the community .
Till such time , we have to fall back on the available surgical approach in control of senile cataract . | Matching Sentences: [ Sen. 1, subscore: 2.00 ]: PURPOSE : Senile cataract contributes to 75% of blindness in India and there is a growing backlog of cataract cases needing surgery . [ Sen. 2, subscore: 2.00 ]: The present study seeks clues to the etiology of senile cataract , so that strategies to prevent or even delay cataract formation could be planned . [ Sen. 9, subscore: 2.00 ]: Though the study provided some clues to the etiology of senile cataract , further studies are needed to know the specific role of these factors in the causation of cataract , so that any preventive or control measures could be initiated in the community . [ Sen. 5, subscore: 1.00 ]: Logistic regression analysis technique was employed to study the associations between senile cataract and various variables . [ Sen. 6, subscore: 1.00 ]: RESULTS : Systolic blood pressure , duration of exposure to sunlight per day were associated with senile cataract in both the centres ( OR = 1 . 4 & 1 . 5 for systolic BP and 1 . 6 & 1 . 4 for exposure to sunlight ) . [ Sen. 7, subscore: 1.00 ]: Utilization of rice gruel ( OR = 0 . 5 ) , duration of exposure to fire & dust per day ( OR = 1 . 8 ) , family history of cataract ( OR = 5 . 0 ) , use of cheap cooking fuels ( OR = 1 . 8 ) , increased height ( OR = 0 . 7 ) and increased number of hours of work per day ( OR = 0 . 7 ) were other variables that showed significant association in either of the centres . [ Sen. 8, subscore: 1.00 ]: CONCLUSION : Senile cataract appears to have a multi factorial etiology . [ Sen. 10, subscore: 1.00 ]: Till such time , we have to fall back on the available surgical approach in control of senile cataract .
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Score: 10.00 | Title: Cloning and characterization of the rice CatA catalase gene , a homologue of the maize Cat3 gene .
| Author: Higo K Higo H | Journal: Plant Mol . Biol . Citation: V : 30 ( 3 ) P : 505-21 Year: 1996 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub8605302 Accession (PMID): 8605302 | Abstract: We isolated and sequenced a genomic clone ( CatA ) encoding CAT-A catalase , a homologue of the maize catalase isozyme 3 ( CAT-3 ) from rice ( Oryza sativa L ) .
The 5-upstream non-coding region had very low similarity with the maize Cat3 gene and possible cis elements and sequence motifs in the maize Cat3 gene were not evident , except for TATA and CAAT motifs .
Several sequence motifs found in the promoters of plant seed-specific genes were identified in the 5-upstream non-coding region of the CatA gene .
Northern blotting showed that the CatA gene is expressed at high levels in seeds during early development and also in young seedlings .
Methyl viologen ( paraquat ) resulted in the 3-fold induction of the CatA gene in the leaves of young seedlings , whereas abscisic acid , wounding , salicylic acid , and hydrogen peroxide had no or only slight effects .
The 1 . 9 kb 5-upstream fragment ( -1559 to +342 ) of the CatA gene was fused with the Escherichia coli beta-glucuronidase ( GUS ) gene and introduced by electroporation into protoplasts prepared from rice suspension-cultured cells , then the transient expression of the GUS gene was examined .
Deletion analysis of this chimeric gene suggested that a weak silencer is located in the region between -1564 to -699 .
Abscisic acid ( ABA ) at a final concentration of 10 ( -6 ) M doubled GUS activity in protoplasts electroporated with the chimeric DNAs having 1 . 9 to 1 . 2 kb 5-upstream regions .
A sequence highly similar to the Sph box , a motif found in genes modulated by ABA , was found at -266 to -254 .
Deletion of this region however , did not eliminate the responsiveness to ABA .
Expression of the chimeric gene in the protoplasts was not enhanced by stress such as low and high temperature , hydrogen peroxide , methyl viologen , salicylic acid , elicitor , and UV light .
The chimeric CatA-GUS plasmid DNAs amplified in the methylation-positive strain , E coli DH5alpha , showed GUS gene activities , whereas all the chimeric DNAs amplified in the methylation-deficient E coli JM110 were completely inactive in the presence or absence of ABA in the culture medium .
DNA methylation , especially of either one or both of the deoxyadenosines at the two GATC motifs ( one in the first exon and the other in the first intron of the rice CatA gene ) , appeared to be responsible for the CatA promoter activity identified in the transient assay . | Matching Sentences: [ Sen. 1, subscore: 3.00 ]: We isolated and sequenced a genomic clone ( CatA ) encoding CAT-A catalase , a homologue of the maize catalase isozyme 3 ( CAT-3 ) from rice ( Oryza sativa L ) . [ Sen. 13, subscore: 2.00 ]: DNA methylation , especially of either one or both of the deoxyadenosines at the two GATC motifs ( one in the first exon and the other in the first intron of the rice CatA gene ) , appeared to be responsible for the CatA promoter activity identified in the transient assay . [ Sen. 3, subscore: 1.00 ]: Several sequence motifs found in the promoters of plant seed-specific genes were identified in the 5-upstream non-coding region of the CatA gene . [ Sen. 4, subscore: 1.00 ]: Northern blotting showed that the CatA gene is expressed at high levels in seeds during early development and also in young seedlings . [ Sen. 5, subscore: 1.00 ]: Methyl viologen ( paraquat ) resulted in the 3-fold induction of the CatA gene in the leaves of young seedlings , whereas abscisic acid , wounding , salicylic acid , and hydrogen peroxide had no or only slight effects . [ Sen. 6, subscore: 1.00 ]: The 1 . 9 kb 5-upstream fragment ( -1559 to +342 ) of the CatA gene was fused with the Escherichia coli beta-glucuronidase ( GUS ) gene and introduced by electroporation into protoplasts prepared from rice suspension-cultured cells , then the transient expression of the GUS gene was examined . [ Sen. 12, subscore: 1.00 ]: The chimeric CatA-GUS plasmid DNAs amplified in the methylation-positive strain , E coli DH5alpha , showed GUS gene activities , whereas all the chimeric DNAs amplified in the methylation-deficient E coli JM110 were completely inactive in the presence or absence of ABA in the culture medium .
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Score: 7.00 | Title: The role of catalase-peroxidase secreted by Magnaporthe oryzae during early infection of rice cells .
| Author: Tanabe S Ishii-Minami N Saitoh K Otake Y Kaku H Shibuya N Nishizawa Y Minami E | Journal: Mol Plant Microbe Interact Citation: V : 24 P : 163-71 Year: 2011 Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub21043575 Accession (PMID): 21043575 | Abstract: The biological role of a secretory catalase of the rice blast fungus Magnaporthe oryzae was studied .
The internal amino acid sequences of the partially purified catalase in the culture filtrate enabled us to identify its encoding gene as a catalase-peroxidase gene , CPXB , among four putative genes for catalase or catalase-peroxidase in M oryzae .
Knockout of the gene drastically reduced the level of catalase activity in the culture filtrate and supernatant of conidial suspension ( SCS ) , and increased the sensitivity to exogenously added HO compared with control strains , suggesting that CPXB is the major gene encoding the secretory catalase and confers resistance to HO in hyphae .
In the mutant , the rate of appressoria that induced accumulation of HO in epidermal cells of the leaf sheath increased and infection at early stages was delayed ; however , the formation of lesions in the leaf blade was not affected compared with the control strain .
These phenotypes were complimented by reintroducing the putative coding regions of CPXB driven by a constitutive promoter .
These results suggest that CPXB plays a role in fungal defense against HO accumulated in epidermal cells of rice at the early stage of infection but not in pathogenicity of M oryzae .
| Matching Sentences: [ Sen. 2, subscore: 4.00 ]: The internal amino acid sequences of the partially purified catalase in the culture filtrate enabled us to identify its encoding gene as a catalase-peroxidase gene , CPXB , among four putative genes for catalase or catalase-peroxidase in M oryzae . [ Sen. 3, subscore: 2.00 ]: Knockout of the gene drastically reduced the level of catalase activity in the culture filtrate and supernatant of conidial suspension ( SCS ) , and increased the sensitivity to exogenously added HO compared with control strains , suggesting that CPXB is the major gene encoding the secretory catalase and confers resistance to HO in hyphae . [ Sen. 1, subscore: 1.00 ]: The biological role of a secretory catalase of the rice blast fungus Magnaporthe oryzae was studied .
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Score: 7.00 | Title: Cloning and characterization of catalases from rice , Oryza sativa L | Author: Wutipraditkul N Boonkomrat S Buaboocha T | Journal: Biosci Biotechnol Biochem Citation: V : 75 P : 1900-6 Year: 2011 Type: In-Process | Literature: oryza Field: abstract Doc ID: pub21979082 Accession (PMID): 21979082 | Abstract: Catalase is the major H ( 2 ) O ( 2 ) -scavenging enzyme in all aerobic organisms .
From the cDNA sequences of three rice ( Oryza sativa L ) genes that encode for predicted catalases ( OsCatA , OsCatB , and OsCatC ) , complete ORFs were subcloned into pET21a and expressed as ( His ) ( 6 ) -tagged proteins in Escherichia coli .
The recombinant ( His ) ( 6 ) -polypeptides were enriched to apparent homogeneity and characterized .
With H ( 2 ) O ( 2 ) as substrate , the highest catalase k ( cat ) value ( 20+/-1 . 71x10 ( -3 ) min ( -1 ) ) was found in recombinant OsCatB .
The optimum temperatures for catalase activity were 30 degrees C for OsCatA and OsCatC and 25 degrees C for OsCatB , while the pH optima were 8 . 0 , 7 . 5 , and 7 . 0 for OsCatA , OsCatB , and OsCatC respectively .
All the catalases were inhibited by sodium azide , beta-mercaptoethanol , and potassium cyanide , but only weakly by 3-amino-1 , 2 , 4-triazole .
The various catalases exhibited different catalase activities in the presence of different salts at different concentrations , OsCatC showing higher salt inhibitory effects than the two other OsCats .
| Matching Sentences: [ Sen. 7, subscore: 2.00 ]: The various catalases exhibited different catalase activities in the presence of different salts at different concentrations , OsCatC showing higher salt inhibitory effects than the two other OsCats . [ Sen. 1, subscore: 1.00 ]: Catalase is the major H ( 2 ) O ( 2 ) -scavenging enzyme in all aerobic organisms . [ Sen. 2, subscore: 1.00 ]: From the cDNA sequences of three rice ( Oryza sativa L ) genes that encode for predicted catalases ( OsCatA , OsCatB , and OsCatC ) , complete ORFs were subcloned into pET21a and expressed as ( His ) ( 6 ) -tagged proteins in Escherichia coli . [ Sen. 4, subscore: 1.00 ]: With H ( 2 ) O ( 2 ) as substrate , the highest catalase k ( cat ) value ( 20+/-1 . 71x10 ( -3 ) min ( -1 ) ) was found in recombinant OsCatB . [ Sen. 5, subscore: 1.00 ]: The optimum temperatures for catalase activity were 30 degrees C for OsCatA and OsCatC and 25 degrees C for OsCatB , while the pH optima were 8 . 0 , 7 . 5 , and 7 . 0 for OsCatA , OsCatB , and OsCatC respectively . [ Sen. 6, subscore: 1.00 ]: All the catalases were inhibited by sodium azide , beta-mercaptoethanol , and potassium cyanide , but only weakly by 3-amino-1 , 2 , 4-triazole .
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Score: 7.00 | Title: Intron loss and gain during evolution of the catalase gene family in angiosperms .
| Author: Frugoli JA McPeek MA Thomas TL McClung CR .
| Journal: Genetics Citation: V : 149 ( 1 ) P : 355-65 Year: 1998 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub9584109 Accession (PMID): 9584109 | Abstract: Angiosperms ( flowering plants ) , including both monocots and dicots , contain small catalase gene families .
In the dicot , Arabidopsis thaliana , two catalase ( CAT ) genes , CAT1 and CAT3 , are tightly linked on chromosome 1 and a third , CAT2 , which is more similar to CAT1 than to CAT3 , is unlinked on chromosome 4 .
Comparison of positions and numbers of introns among 13 angiosperm catalase genomic sequences indicates that intron positions are conserved , and suggests that an ancestral catalase gene common to monocots and dicots contained seven introns .
Arabidopsis CAT2 has seven introns ; both CAT1 and CAT3 have six introns in positions conserved with CAT2 , but each has lost a different intron .
We suggest the following sequence of events during the evolution of the Arabidopsis catalase gene family .
An initial duplication of an ancestral catalase gene gave rise to CAT3 and CAT1 .
CAT1 then served as the template for a second duplication , yielding CAT2 .
Intron losses from CAT1 and CAT3 followed these duplications .
One subclade of monocot catalases has lost all but the 5-most and 3-most introns , which is consistent with a mechanism of intron loss by replacement of an ancestral intron-containing gene with a reverse-transcribed DNA copy of a fully spliced mRNA .
Following this event of concerted intron loss , the Oryza sativa ( rice , a monocot ) CAT1 lineage acquired an intron in a novel position , consistent with a mechanism of intron gain at proto-splice sites . | Matching Sentences: [ Sen. 3, subscore: 2.00 ]: Comparison of positions and numbers of introns among 13 angiosperm catalase genomic sequences indicates that intron positions are conserved , and suggests that an ancestral catalase gene common to monocots and dicots contained seven introns . [ Sen. 1, subscore: 1.00 ]: Angiosperms ( flowering plants ) , including both monocots and dicots , contain small catalase gene families . [ Sen. 2, subscore: 1.00 ]: In the dicot , Arabidopsis thaliana , two catalase ( CAT ) genes , CAT1 and CAT3 , are tightly linked on chromosome 1 and a third , CAT2 , which is more similar to CAT1 than to CAT3 , is unlinked on chromosome 4 . [ Sen. 5, subscore: 1.00 ]: We suggest the following sequence of events during the evolution of the Arabidopsis catalase gene family . [ Sen. 6, subscore: 1.00 ]: An initial duplication of an ancestral catalase gene gave rise to CAT3 and CAT1 . [ Sen. 9, subscore: 1.00 ]: One subclade of monocot catalases has lost all but the 5-most and 3-most introns , which is consistent with a mechanism of intron loss by replacement of an ancestral intron-containing gene with a reverse-transcribed DNA copy of a fully spliced mRNA .
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Score: 6.00 | Title: Complementation of yeast Arc1p by the p43 component of the human multisynthetase complex does not require its association with yeast MetRS and GluRS .
| Author: Golinelli-Cohen MP Zakrzewska A Mirande M | Journal: J Mol . Biol . Citation: V : 340 ( 1 ) P : 15-27 Year: 2004 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub15184019 Accession (PMID): 15184019 | Abstract: Yeast Arc1p , human p43 and plant methionyl-tRNA synthetase ( MetRS ) possess an EMAPII-like domain capable of non-specific interactions with tRNA .
Arc1p interacts with MetRS ( MES1 ) and GluRS and operates as a tRNA-interacting factor ( tIF ) in trans of these two synthetases .
In plant MetRS , the EMAPII-like domain is fused to the catalytic core of the synthetase and acts as a cis-acting tIF for aminoacylation .
We observed that the catalytic core of plant MetRS expressed from a centromeric plasmid can not complement a yeast arc1 ( - ) mes1 ( - ) strain .
Overexpression of the mutant enzyme from a high-copy number plasmid restored cell growth , suggesting that deletion of its C-terminal tIF domain was responsible for the poor aminoacylation efficiency of that enzyme in vivo .
Accordingly , expression of full-size plant MetRS from a centromeric plasmid , but also of fusion proteins between its catalytic core and the EMAPII-like domains of yeast Arc1p or of human p43 restored cell viability .
These data showed that homologous tIF domains from different origins are interchangeable and may act indifferently in trans or in cis of the catalytic domain of a synthetase .
Unexpectedly , co-expression of Arc1p with the catalytic core of plant MetRS restored cell viability as well , even though Arc1p did not associate with plant MetRS .
Because Arc1p also interacts with yeast GluRS , restoration of cell growth could be due at least in part to its role of cofactor for that enzyme .
However , co-expression of human p43 , a tIF that did not associate with plant MetRS or with yeast GluRS and MetRS , also restored cell viability of a yeast strain that expressed the catalytic core of plant MetRS .
These results show that p43 and Arc1p are able to facilitate tRNA aminoacylation in vivo even if they do not interact physically with the synthetases .
We propose that p43/Arc1p may be involved in sequestering tRNAs in the cytoplasm of eukaryotic cells , thereby increasing their availability for protein synthesis . | Matching Sentences: [ Sen. 3, subscore: 1.00 ]: In plant MetRS , the EMAPII-like domain is fused to the catalytic core of the synthetase and acts as a cis-acting tIF for aminoacylation . [ Sen. 4, subscore: 1.00 ]: We observed that the catalytic core of plant MetRS expressed from a centromeric plasmid can not complement a yeast arc1 ( - ) mes1 ( - ) strain . [ Sen. 6, subscore: 1.00 ]: Accordingly , expression of full-size plant MetRS from a centromeric plasmid , but also of fusion proteins between its catalytic core and the EMAPII-like domains of yeast Arc1p or of human p43 restored cell viability . [ Sen. 7, subscore: 1.00 ]: These data showed that homologous tIF domains from different origins are interchangeable and may act indifferently in trans or in cis of the catalytic domain of a synthetase . [ Sen. 8, subscore: 1.00 ]: Unexpectedly , co-expression of Arc1p with the catalytic core of plant MetRS restored cell viability as well , even though Arc1p did not associate with plant MetRS . [ Sen. 10, subscore: 1.00 ]: However , co-expression of human p43 , a tIF that did not associate with plant MetRS or with yeast GluRS and MetRS , also restored cell viability of a yeast strain that expressed the catalytic core of plant MetRS .
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Score: 6.00 | Title: Catalysis by Glomerella cingulata cutinase requires conformational cycling between the active and inactive states of its catalytic triad .
| Author: Nyon MP Rice DW Berrisford JM Hounslow AM Moir AJ Huang H Nathan S Mahadi NM Bakar FD Craven CJ | Journal: J Mol Biol Citation: V : 385 P : 226-35 Year: 2009 Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub18983850 Accession (PMID): 18983850 | Abstract: Cutinase belongs to a group of enzymes that catalyze the hydrolysis of esters and triglycerides .
Structural studies on the enzyme from Fusarium solani have revealed the presence of a classic catalytic triad that has been implicated in the enzymes mechanism .
We have solved the crystal structure of Glomerella cingulata cutinase in the absence and in the presence of the inhibitors E600 ( diethyl p-nitrophenyl phosphate ) and PETFP ( 3-phenethylthio-1 , 1 , 1-trifluoropropan-2-one ) to resolutions between 2 . 6 and 1 . 9 A Analysis of these structures reveals that the catalytic triad ( Ser136 , Asp191 , and His204 ) adopts an unusual configuration with the putative essential histidine His204 swung out of the active site into a position where it is unable to participate in catalysis , with the imidazole ring 11 A away from its expected position .
Solution-state NMR experiments are consistent with the disrupted configuration of the triad observed crystallographically .
H204N , a site-directed mutant , was shown to be catalytically inactive , confirming the importance of this residue in the enzyme mechanism .
These findings suggest that , during its catalytic cycle , cutinase undergoes a significant conformational rearrangement converting the loop bearing the histidine from an inactive conformation , in which the histidine of the triad is solvent exposed , to an active conformation , in which the triad assumes a classic configuration .
| Matching Sentences: [ Sen. 3, subscore: 2.00 ]: We have solved the crystal structure of Glomerella cingulata cutinase in the absence and in the presence of the inhibitors E600 ( diethyl p-nitrophenyl phosphate ) and PETFP ( 3-phenethylthio-1 , 1 , 1-trifluoropropan-2-one ) to resolutions between 2 . 6 and 1 . 9 A Analysis of these structures reveals that the catalytic triad ( Ser136 , Asp191 , and His204 ) adopts an unusual configuration with the putative essential histidine His204 swung out of the active site into a position where it is unable to participate in catalysis , with the imidazole ring 11 A away from its expected position . [ Sen. 1, subscore: 1.00 ]: Cutinase belongs to a group of enzymes that catalyze the hydrolysis of esters and triglycerides . [ Sen. 2, subscore: 1.00 ]: Structural studies on the enzyme from Fusarium solani have revealed the presence of a classic catalytic triad that has been implicated in the enzymes mechanism . [ Sen. 5, subscore: 1.00 ]: H204N , a site-directed mutant , was shown to be catalytically inactive , confirming the importance of this residue in the enzyme mechanism . [ Sen. 6, subscore: 1.00 ]: These findings suggest that , during its catalytic cycle , cutinase undergoes a significant conformational rearrangement converting the loop bearing the histidine from an inactive conformation , in which the histidine of the triad is solvent exposed , to an active conformation , in which the triad assumes a classic configuration .
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