499 matches found in 345 documents. Search time: 0.035 seconds. |
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Score: 11.00 | Title: Infrared photodissociation of a water molecule from a flexible molecule-H ( 2 ) O complex : Rates and conformational product yields following XH stretch excitation .
| Author: Clarkson JR Herbert JM Zwier TS .
| Journal: Year: 2007 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub17430031 Accession (PMID): 17430031 | Abstract: Infrared-ultraviolet hole-burning and hole-filling spectroscopies have been used to study IR-induced dissociation of the tryptamineH ( 2 ) O and tryptamineD ( 2 ) O complexes .
Upon complexation of a single water molecule , the seven conformational isomers of tryptamine collapse to a single structure that retains the same ethylamine side chain conformation present in the most highly populated conformer of tryptamine monomer .
Infrared excitation of the tryptamineH ( 2 ) O complex was carried out using a series of infrared absorptions spanning the range of 2470-3715 cm ( -1 ) .
The authors have determined the conformational product yield over this range and the dissociation rate near threshold , where it is slow enough to be measured by our methods .
The observed threshold for dissociation occurred at 2872 cm ( -1 ) in tryptamineH ( 2 ) O and at 2869 cm ( -1 ) in tryptamineD ( 2 ) O , with no dissociation occurring on the time scale of the experiment ( approximately 2 mus ) at 2745 cm ( -1 ) .
The dissociation time constants varied from approximately 200 ns for the 2869 cm ( -1 ) band of tryptamineD ( 2 ) O to approximately 25 ns for the 2872 cm ( -1 ) band of tryptamineH ( 2 ) O This large isotope dependence is associated with a zero-point energy effect that increases the binding energy of the deuterated complex by approximately 190 cm ( -1 ) , thereby reducing the excess energy available at the same excitation energy .
At all higher energies , the dissociation lifetime was shorter than the pulse duration of our lasers ( 8 ns ) .
At all wavelengths , the observed products in the presence of collisions are dominated by conformers A and B of tryptamine monomer , with small contributions from the other minor conformers .
In addition , right at threshold ( 2869 cm ( -1 ) ) , tryptamineD ( 2 ) O dissociates exclusively to conformer A in the absence of collisions with helium , while both A and B conformational products are observed in the presence of collisions with helium .
Using resolution-of-identity approximation to second-order Moller-Plesset binding energies extrapolated to the complete basis set limit and harmonic vibrational frequencies and transition states calculated at the density functional limit B3LYP6-31+G ( * ) level of theory , Rice-Ramsperger-Kassel-Marcus ( RRKM ) predictions for the dissociation , isomerization , and water shuttling rates as a function of energy are made .
At threshold , the experimental dissociation rate is almost 10 ( 3 ) faster than RRKM predictions .
Reasons for this apparent non-RRKM behavior will be discussed .
| Matching Sentences: [ Sen. 1, subscore: 2.00 ]: Infrared-ultraviolet hole-burning and hole-filling spectroscopies have been used to study IR-induced dissociation of the tryptamineH ( 2 ) O and tryptamineD ( 2 ) O complexes . [ Sen. 2, subscore: 2.00 ]: Upon complexation of a single water molecule , the seven conformational isomers of tryptamine collapse to a single structure that retains the same ethylamine side chain conformation present in the most highly populated conformer of tryptamine monomer . [ Sen. 5, subscore: 2.00 ]: The observed threshold for dissociation occurred at 2872 cm ( -1 ) in tryptamineH ( 2 ) O and at 2869 cm ( -1 ) in tryptamineD ( 2 ) O , with no dissociation occurring on the time scale of the experiment ( approximately 2 mus ) at 2745 cm ( -1 ) . [ Sen. 6, subscore: 2.00 ]: The dissociation time constants varied from approximately 200 ns for the 2869 cm ( -1 ) band of tryptamineD ( 2 ) O to approximately 25 ns for the 2872 cm ( -1 ) band of tryptamineH ( 2 ) O This large isotope dependence is associated with a zero-point energy effect that increases the binding energy of the deuterated complex by approximately 190 cm ( -1 ) , thereby reducing the excess energy available at the same excitation energy . [ Sen. 3, subscore: 1.00 ]: Infrared excitation of the tryptamineH ( 2 ) O complex was carried out using a series of infrared absorptions spanning the range of 2470-3715 cm ( -1 ) . [ Sen. 8, subscore: 1.00 ]: At all wavelengths , the observed products in the presence of collisions are dominated by conformers A and B of tryptamine monomer , with small contributions from the other minor conformers . [ Sen. 9, subscore: 1.00 ]: In addition , right at threshold ( 2869 cm ( -1 ) ) , tryptamineD ( 2 ) O dissociates exclusively to conformer A in the absence of collisions with helium , while both A and B conformational products are observed in the presence of collisions with helium .
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Score: 10.00 | Title: In vitro inhibition of the activation of Pro-matrix Metalloproteinase 1 ( Pro-MMP-1 ) and Pro-matrix metalloproteinase 9 ( Pro-MMP-9 ) by rice and soybean Bowman-Birk inhibitors .
| Author: Bawadi HA Antunes TM Shih F Losso JN .
| Journal: J Agric .
Food Chem .
Year: 2004 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub15264907 Accession (PMID): 15264907 | Abstract: The in vitro inhibitory activity of the rice Bowman-Birk inhibitor ( rBBI ) or soybean Bowman-Birk inhibitor ( sBBI ) against trypsin-catalyzed activation of pro-matrix metalloproteinase 1 or 9 ( pro-MMP-1 or pro-MMP-9 ) , respectively , was investigated using electrophoresis with silver staining , heparin-enhanced zymography , biotinylated gelatin , Biotrak assay , and fluorescence quenched substrate hydrolysis . rBBI at concentrations of 0 . 08-0 . 352 mg/mL dose-dependently inhibited the in vitro activation of 45 microg/mL pro-MMP-1 by trypsin .
Heparin-enhanced zymography analysis of pro-MMP-1 , trypsin-activated MMP-1 , and a mixture of pro-MMP-1-trypsin-rBBI showed clear zones associated with trypsin-activated MMP-1 and the absence of clear zones in lanes containing pro-MMP-1 or a mixture of pro-MMP-1 , trypsin , and rBBI .
The results of the Biotrak assay also indicated that rBBI dose-dependently suppressed the activation of pro-MMP-1 by trypsin . sBBI dose-dependently inhibited the activation of 100 microg/mL of pro-MMP-9 by trypsin .
Biotinylated gelatin assays demonstrated that pro-MMP-9 or pro-MMP-9 in the presence of trypsin and BBI did not hydrolyze gelatin , whereas p-aminophenylmercury acetate ( APMA ) -activated MMP-9 and trypsin-activated MMP-9 caused significant hydrolysis of gelatin .
Quenched fluorescence substrate hydrolysis for total MMP activity showed that pro-MMP-1 or pro-MMP-9 did not hydrolyze the substrate Mca-Pro-Leu-Gly-Leu-Dpa-Ala-Arg-NH2 ; active MMP-1 or MMP-9 hydrolyzed the substrate , but lower substrate hydrolysis was obtained when pro-MMP-1 or pro-MMP-9 was incubated with trypsin in the presence of increasing concentrations of rBBI .
The results are discussed in light of the role of MMP-1 and MMP-9 in the process of angiogenesis and the potential of rBBI or sBBI as a functional food ingredient . | Matching Sentences: [ Sen. 2, subscore: 3.00 ]: Heparin-enhanced zymography analysis of pro-MMP-1 , trypsin-activated MMP-1 , and a mixture of pro-MMP-1-trypsin-rBBI showed clear zones associated with trypsin-activated MMP-1 and the absence of clear zones in lanes containing pro-MMP-1 or a mixture of pro-MMP-1 , trypsin , and rBBI . [ Sen. 1, subscore: 2.00 ]: The in vitro inhibitory activity of the rice Bowman-Birk inhibitor ( rBBI ) or soybean Bowman-Birk inhibitor ( sBBI ) against trypsin-catalyzed activation of pro-matrix metalloproteinase 1 or 9 ( pro-MMP-1 or pro-MMP-9 ) , respectively , was investigated using electrophoresis with silver staining , heparin-enhanced zymography , biotinylated gelatin , Biotrak assay , and fluorescence quenched substrate hydrolysis . rBBI at concentrations of 0 . 08-0 . 352 mg/mL dose-dependently inhibited the in vitro activation of 45 microg/mL pro-MMP-1 by trypsin . [ Sen. 3, subscore: 2.00 ]: The results of the Biotrak assay also indicated that rBBI dose-dependently suppressed the activation of pro-MMP-1 by trypsin . sBBI dose-dependently inhibited the activation of 100 microg/mL of pro-MMP-9 by trypsin . [ Sen. 4, subscore: 2.00 ]: Biotinylated gelatin assays demonstrated that pro-MMP-9 or pro-MMP-9 in the presence of trypsin and BBI did not hydrolyze gelatin , whereas p-aminophenylmercury acetate ( APMA ) -activated MMP-9 and trypsin-activated MMP-9 caused significant hydrolysis of gelatin . [ Sen. 5, subscore: 1.00 ]: Quenched fluorescence substrate hydrolysis for total MMP activity showed that pro-MMP-1 or pro-MMP-9 did not hydrolyze the substrate Mca-Pro-Leu-Gly-Leu-Dpa-Ala-Arg-NH2 ; active MMP-1 or MMP-9 hydrolyzed the substrate , but lower substrate hydrolysis was obtained when pro-MMP-1 or pro-MMP-9 was incubated with trypsin in the presence of increasing concentrations of rBBI .
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Score: 10.00 | Title: Probing the role of tryptophan-derived secondary metabolism in defense responses against Bipolaris oryzae infection in rice leaves by a suicide substrate of tryptophan decarboxylase .
| Author: Ishihara A Nakao T Mashimo Y Murai M Ichimaru N Tanaka C Nakajima H Wakasa K Miyagawa H | Journal: Phytochemistry Year: 2011 Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub21112065 Accession (PMID): 21112065 | Abstract: Tryptophan-derived secondary metabolites , including serotonin and its hydroxycinnamic acid amides , markedly accumulate in rice leaves in response to pathogen attack .
These compounds have been implicated in the physical defense system against pathogen invasion by being deposited in cell walls .
Serotonin is biosynthesized from tryptophan via tryptamine , and tryptophan decarboxylase ( TDC ) catalyzes the first committed reaction .
In this study , ( S ) -alpha- ( fluoromethyl ) tryptophan ( S-alphaFMT ) was utilized to investigate the effects of the inhibition of TDC on the defense responses of rice leaves .
S-alphaFMT , enantiospecifically synthesized from L-tryptophan , effectively inhibited TDC activity extracted from rice leaves infected by Bipolaris oryzae .
The inhibition rate increased dependently on the incubation time , indicating that S-alphaFMT served as a suicide substrate .
Treatment of rice seedlings with S-alphaFMT suppressed accumulation of serotonin , tryptamine , and hydroxycinnamic acid amides of serotonin in a dose-dependent manner in B oryzae-inoculated leaves .
The lesions formed on seedlings treated with S-alphaFMT lacked deposition of brown materials , and those leaves were severely damaged in comparison with leaves without S-alphaFMT treatment .
Administrating tryptamine to S-alphaFMT-treated leaves restored accumulation of tryptophan-derived secondary metabolites as well as deposition of brown material In addition , tryptamine administration reduced damage caused by fungal infection .
Accordingly , the accumulation of tryptophan-derived secondary metabolites was suggested to be part of the effective defense mechanism of rice .
| Matching Sentences: [ Sen. 3, subscore: 3.00 ]: Serotonin is biosynthesized from tryptophan via tryptamine , and tryptophan decarboxylase ( TDC ) catalyzes the first committed reaction . [ Sen. 9, subscore: 3.00 ]: Administrating tryptamine to S-alphaFMT-treated leaves restored accumulation of tryptophan-derived secondary metabolites as well as deposition of brown material In addition , tryptamine administration reduced damage caused by fungal infection . [ Sen. 1, subscore: 1.00 ]: Tryptophan-derived secondary metabolites , including serotonin and its hydroxycinnamic acid amides , markedly accumulate in rice leaves in response to pathogen attack . [ Sen. 4, subscore: 1.00 ]: In this study , ( S ) -alpha- ( fluoromethyl ) tryptophan ( S-alphaFMT ) was utilized to investigate the effects of the inhibition of TDC on the defense responses of rice leaves . [ Sen. 7, subscore: 1.00 ]: Treatment of rice seedlings with S-alphaFMT suppressed accumulation of serotonin , tryptamine , and hydroxycinnamic acid amides of serotonin in a dose-dependent manner in B oryzae-inoculated leaves . [ Sen. 10, subscore: 1.00 ]: Accordingly , the accumulation of tryptophan-derived secondary metabolites was suggested to be part of the effective defense mechanism of rice .
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Score: 7.00 | Title: Identification of target genes conferring ethanol stress tolerance to Saccharomyces cerevisiae based on DNA microarray data analysis .
| Author: Hirasawa T Yoshikawa K Nakakura Y Nagahisa K Furusawa C Katakura Y Shimizu H Shioya S | Journal: J Biotechnol Year: 2007 Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub17604866 Accession (PMID): 17604866 | Abstract: During industrial production process using yeast , cells are exposed to the stress due to the accumulation of ethanol , which affects the cell growth activity and productivity of target products , thus , the ethanol stress-tolerant yeast strains are highly desired .
To identify the target gene ( s ) for constructing ethanol stress tolerant yeast strains , we obtained the gene expression profiles of two strains of Saccharomyces cerevisiae , namely , a laboratory strain and a strain used for brewing Japanese rice wine ( sake ) , in the presence of 5% ( v/v ) ethanol , using DNA microarray .
For the selection of target genes for breeding ethanol stress tolerant strains , clustering of DNA microarray data was performed .
For further selection , the ethanol sensitivity of the knockout mutants in each of which the gene selected by DNA microarray analysis is deleted , was also investigated .
The integration of the DNA microarray data and the ethanol sensitivity data of knockout strains suggests that the enhancement of expression of genes related to tryptophan biosynthesis might confer the ethanol stress tolerance to yeast cells .
Indeed , the strains overexpressing tryptophan biosynthesis genes showed a stress tolerance to 5% ethanol .
Moreover , the addition of tryptophan to the culture medium and overexpression of tryptophan permease gene conferred ethanol stress tolerance to yeast cells .
These results indicate that overexpression of the genes for trypophan biosynthesis increases the ethanol stress tolerance .
Tryptophan supplementation to culture and overexpression of the tryptophan permease gene are also effective for the increase in ethanol stress tolerance .
Our methodology for the selection of target genes for constructing ethanol stress tolerant strains , based on the data of DNA microarray analysis and phenotypes of knockout mutants , was validated .
| Matching Sentences: [ Sen. 7, subscore: 2.00 ]: Moreover , the addition of tryptophan to the culture medium and overexpression of tryptophan permease gene conferred ethanol stress tolerance to yeast cells . [ Sen. 9, subscore: 2.00 ]: Tryptophan supplementation to culture and overexpression of the tryptophan permease gene are also effective for the increase in ethanol stress tolerance . [ Sen. 5, subscore: 1.00 ]: The integration of the DNA microarray data and the ethanol sensitivity data of knockout strains suggests that the enhancement of expression of genes related to tryptophan biosynthesis might confer the ethanol stress tolerance to yeast cells . [ Sen. 6, subscore: 1.00 ]: Indeed , the strains overexpressing tryptophan biosynthesis genes showed a stress tolerance to 5% ethanol . [ Sen. 8, subscore: 1.00 ]: These results indicate that overexpression of the genes for trypophan biosynthesis increases the ethanol stress tolerance .
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Score: 7.00 | Title: Serotonin accumulation in transgenic rice by over-expressing tryptophan decarboxylase results in a dark brown phenotype and stunted growth .
| Author: Kanjanaphachoat P Wei BY Lo SF Wang IW Wang CS Yu SM Yen ML Chiu SH Lai CC Chen LJ | Journal: Plant Mol Biol Year: 2012 Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub22297847 Accession (PMID): 22297847 | Abstract: A mutant M47286 with a stunted growth , low fertility and dark-brown phenotype was identified from a T-DNA-tagged rice mutant library .
This mutant contained a copy of the T-DNA tag inserted at the location where the expression of two putative tryptophan decarboxylase genes , TDC-1 and TDC-3 , were activated .
Enzymatic assays of both recombinant proteins showed tryptophan decarboxylase activities that converted tryptophan to tryptamine , which could be converted to serotonin by a constitutively expressed tryptamine 5 hydroxylase ( T5H ) in rice plants .
Over-expression of TDC-1 and TDC-3 in transgenic rice recapitulated the stunted growth , darkbrown phenotype and resulted in a low fertility similar to M47286 .
The degree of stunted growth and dark-brown color was proportional to the expression levels of TDC-1 and TDC-3 .
The levels of tryptamine and serotonin accumulation in these transgenic rice lines were also directly correlated with the expression levels of TDC-1 and TDC-3 .
A mass spectrometry assay demonstrated that the darkbrown leaves and hulls in the TDC-overexpressing transgenic rice were caused by the accumulation of serotonin dimer and that the stunted growth and low fertility were also caused by the accumulation of serotonin and serotonin dimer , but not tryptamine .
These results represent the first evidence that over-expression of TDC results in stunted growth , low fertility and the accumulation of serotonin , which when converted to serotonin dimer , leads to a dark brown plant color .
| Matching Sentences: [ Sen. 3, subscore: 4.00 ]: Enzymatic assays of both recombinant proteins showed tryptophan decarboxylase activities that converted tryptophan to tryptamine , which could be converted to serotonin by a constitutively expressed tryptamine 5 hydroxylase ( T5H ) in rice plants . [ Sen. 2, subscore: 1.00 ]: This mutant contained a copy of the T-DNA tag inserted at the location where the expression of two putative tryptophan decarboxylase genes , TDC-1 and TDC-3 , were activated . [ Sen. 6, subscore: 1.00 ]: The levels of tryptamine and serotonin accumulation in these transgenic rice lines were also directly correlated with the expression levels of TDC-1 and TDC-3 . [ Sen. 7, subscore: 1.00 ]: A mass spectrometry assay demonstrated that the darkbrown leaves and hulls in the TDC-overexpressing transgenic rice were caused by the accumulation of serotonin dimer and that the stunted growth and low fertility were also caused by the accumulation of serotonin and serotonin dimer , but not tryptamine .
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Score: 7.00 | Title: Primary structure of 3-phosphoglycerate kinase from horse muscle .
II .
Amino acid sequence of cyanogen bromide peptides CB1-CB4 and CB6-CB14 , sequence of methionine-containing regions , and complete sequence of the enzyme .
| Author: Merrett M | Journal: J Biol . Chem . Year: 1981 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub7287713 Accession (PMID): 7287713 | Abstract: The amino acid sequences of 13 of the 14 cyanogen bromide peptides of horse muscle 3-phosphoglycerate kinase have been determined .
These peptides together constitute 75% of the structure of the enzyme .
Except for the smallest peptides , automated sequence analysis of the parent peptide was employed together with the automated or manual ( 5-dimethylaminonaphthalene-1-sulfonyl ( dansyl ) -Edman method ) sequencing of relevant peptides obtained by proteolytic digestion .
In the case of the five smallest peptides , all between 6 and 11 residues in length , sequences were derived from analyses of the intact peptides .
CB14a , a peptide produced in low yield during the preparation of the cyanogen bromide fragments , was helpful in the sequence analysis of CB14 .
This peptide appeared to have arisen as the result of a cyanogen bromide cleavage on the carboxyl side of a tryptophanyl residue .
The sequences of these 13 cyanogen bromide peptides , together with that of CB1 , reported previously ( Hardy , G W , Darbre , A , and Merrett , M ( 1981 ) J Biol . Chem . 256 , 10284-10292 ) , have been combined with data obtained from the sequence analysis of tryptic peptides derived from the methionine-containing regions of the enzyme to determine the complete sequence .
Isolation of these overlap peptides was facilitated by the labeling of methionyl residues with iodo [ 2-14C ] acetic acid prior to tryptic digestion .
Tryptophan-containing tryptic peptides were also isolated , and their sequence analysis enabled the positions of the four tryptophanyl residues to be established .
In this way , the problem caused by tryptophan degradation during the preparation of the cyanogen bromide fragments was overcome .
The NH2 terminus of CB1 , the NH2-terminal cyanogen bromide peptide , was identified as N-acetyl serine by mass spectrometry .
The alignment of the cyanogen bromide fragments of horse muscle 3-phosphoglycerate kinase described here is in complete agreement with that based on X-ray analysis of the enzyme reported previously ( Banks , R D , Blake , C C F , Evans , P R , Haser , R , Rice , D W , Hardy , G W , Merrett , M , and Phillips , A W ( 1979 ) Nature 279 , 773-777 ) .
The complete structure is comprised of 416 residues and has a molecular weight of 44 , 519 .
| Matching Sentences: [ Sen. 9, subscore: 3.00 ]: Tryptophan-containing tryptic peptides were also isolated , and their sequence analysis enabled the positions of the four tryptophanyl residues to be established . [ Sen. 6, subscore: 1.00 ]: This peptide appeared to have arisen as the result of a cyanogen bromide cleavage on the carboxyl side of a tryptophanyl residue . [ Sen. 7, subscore: 1.00 ]: The sequences of these 13 cyanogen bromide peptides , together with that of CB1 , reported previously ( Hardy , G W , Darbre , A , and Merrett , M ( 1981 ) J Biol . Chem . 256 , 10284-10292 ) , have been combined with data obtained from the sequence analysis of tryptic peptides derived from the methionine-containing regions of the enzyme to determine the complete sequence . [ Sen. 8, subscore: 1.00 ]: Isolation of these overlap peptides was facilitated by the labeling of methionyl residues with iodo [ 2-14C ] acetic acid prior to tryptic digestion . [ Sen. 10, subscore: 1.00 ]: In this way , the problem caused by tryptophan degradation during the preparation of the cyanogen bromide fragments was overcome .
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Score: 7.00 | Title: The tryptophan content in protein of cereal grains and legume seeds as a function of nitrogen content .
A reappraisal of tryptophan score .
| Author: Delhaye S Landry J | Journal: Adv . Exp . Med . Biol . Year: Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub8906341 Accession (PMID): 8906341 | Abstract: The tryptophan content ( [ Trp ] ) in the dry matter ( DM ) of wheat , maize , barley , sorghum , rice , pearl millet grains , pea and broad bean seeds is evaluated from samples , with various nitrogen contents ( [ N ] DM ) and genotypes , using a procedure that has been shown to be strictly quantitative .
The determination of linear correlations between [ Trp ] DM and [ N ] DM , and between the tryptophan content in protein ( [ Trp ] N ) and [ N ] DM or 1/ [ N ] DM for every species leads to the following observations : ( 1 ) [ Trp ] DM and [ N ] DM are linearly related .
The data show that previous reports of similar relationships underestimate tryptophan by 10 +/- 5% owing to tryptophan degradation during alkaline hydrolysis preparatory to analysis ; ( 2 ) the linear correlations between [ Trp ] N and 1/ [ N ] DM , resulting from linear relationships [ Trp ] DM and [ N ] DM display coefficients of determination ( r2 ) far lower than 1 and similar to those found for linear correlations between [ Trp ] N and [ N ] DM ; ( 3 ) [ Trp ] N increases with [ N ] DM increasing for rice and pearl millet while it decreases for all other species .
In conclusion : ( 1 ) linear relationships between tryptophan and nitrogen have a low predictive value ; ( 2 ) the nutritional score of tryptophan of foods and feeds , as calculated from the determination of tryptophan using a procedure involving alkaline hydrolysis , is generally underestimated by 10% .
| Matching Sentences: [ Sen. 4, subscore: 3.00 ]: In conclusion : ( 1 ) linear relationships between tryptophan and nitrogen have a low predictive value ; ( 2 ) the nutritional score of tryptophan of foods and feeds , as calculated from the determination of tryptophan using a procedure involving alkaline hydrolysis , is generally underestimated by 10% . [ Sen. 3, subscore: 2.00 ]: The data show that previous reports of similar relationships underestimate tryptophan by 10 +/- 5% owing to tryptophan degradation during alkaline hydrolysis preparatory to analysis ; ( 2 ) the linear correlations between [ Trp ] N and 1/ [ N ] DM , resulting from linear relationships [ Trp ] DM and [ N ] DM display coefficients of determination ( r2 ) far lower than 1 and similar to those found for linear correlations between [ Trp ] N and [ N ] DM ; ( 3 ) [ Trp ] N increases with [ N ] DM increasing for rice and pearl millet while it decreases for all other species . [ Sen. 1, subscore: 1.00 ]: The tryptophan content ( [ Trp ] ) in the dry matter ( DM ) of wheat , maize , barley , sorghum , rice , pearl millet grains , pea and broad bean seeds is evaluated from samples , with various nitrogen contents ( [ N ] DM ) and genotypes , using a procedure that has been shown to be strictly quantitative . [ Sen. 2, subscore: 1.00 ]: The determination of linear correlations between [ Trp ] DM and [ N ] DM , and between the tryptophan content in protein ( [ Trp ] N ) and [ N ] DM or 1/ [ N ] DM for every species leads to the following observations : ( 1 ) [ Trp ] DM and [ N ] DM are linearly related .
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Score: 6.00 | Title: Characterization of tryptamine 5-hydroxylase and serotonin synthesis in rice plants .
| Author: Kang S Kang K Lee K Back K | Journal: Plant Cell Rep Year: 2007 Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub17639402 Accession (PMID): 17639402 | Abstract: Serotonin is a well-known pineal hormone that in mammals plays a key role in mood .
In plants , serotonin is implicated in several physiological roles such as flowering , morphogenesis , and adaptation to environmental changes .
However , its biosynthetic enzyme in plants has not been characterized .
Therefore , we measured the serotonin content and enzyme activity responsible for serotonin biosynthesis in rice seedlings .
Tryptamine 5-hydroxylase ( T5H ) , which converts tryptamine into serotonin , was found as a soluble enzyme that had maximal activity in the roots .
The maximal activity of T5H was closely associated with the enriched synthesis of serotonin in roots .
Tetrahydropterine-dependent T5H activity was inhibited by tyramine , tryptophan , 5-OH-tryptophan , and octopamine , but remained unaltered by dopamine in vitro .
The it issues of rice seedlings grown in the presence of tryptamine exhibited a dose-dependent increase in serotonin in parallel with enhanced T5H enzyme activity .
However , no significant increase in serotonin was observed in rice it issues grown in the presence of tryptophan , suggesting that tryptamine is a bottleneck intermediate substrate for serotonin synthesis .
| Matching Sentences: [ Sen. 5, subscore: 2.00 ]: Tryptamine 5-hydroxylase ( T5H ) , which converts tryptamine into serotonin , was found as a soluble enzyme that had maximal activity in the roots . [ Sen. 9, subscore: 2.00 ]: However , no significant increase in serotonin was observed in rice it issues grown in the presence of tryptophan , suggesting that tryptamine is a bottleneck intermediate substrate for serotonin synthesis . [ Sen. 7, subscore: 1.00 ]: Tetrahydropterine-dependent T5H activity was inhibited by tyramine , tryptophan , 5-OH-tryptophan , and octopamine , but remained unaltered by dopamine in vitro . [ Sen. 8, subscore: 1.00 ]: The it issues of rice seedlings grown in the presence of tryptamine exhibited a dose-dependent increase in serotonin in parallel with enhanced T5H enzyme activity .
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Score: 6.00 | Title: Overproduction of indole acetic acid in Azospirillum lipoferum using the Escherichia coli trp operon .
| Author: Cho MJ Gal SW Choi YJ Yoon HW Kim CY Hong JC Bahk JD .
| Journal: Microb .
Releases Year: 1993 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub8281358 Accession (PMID): 8281358 | Abstract: A recombinant plasmid carrying the trp operon from Escherichia coli , which synthesizes tryptophan from chorismate , was constructed by using a broad host range plasmid vector pRK290 ; a mutant trp plasmid for tryptophan overproduction was then selected .
The physiological , biochemical , and genetic properties of the Azospirillum lipoferum KY6 , a potential nitrogen fixer of rice , harbouring the recombinant trp plasmid pMJC1 and its mutant pMJC101 , were compared with those of the wild-type bacteria .
Anthranilate synthetase is known to be the trpE gene product which plays a key role in the regulatory step in the feedback control of tryptophan biosynthesis .
The enzyme activity of the Azospirillum lipoferum KY6 carrying pMJC1 or pMJC101 was respectively 7 and 30-fold higher than that of the wild type in the presence of 10 ( -4 ) M tryptophan .
As expected , the amount of tryptophan biosynthesis in A lipoferum KY6 ( pMJC101 ) was increased approximately 100-fold as compared with the wild type , which led to overproduction of indole acetic acid even without addition of exogenous tryptophan .
Moreover , the recombinant trp plasmid was fairly stable in A lipoferum KY6 host , showing only 25% loss of the plasmid itself or the trp insert after 40 generations .
| Matching Sentences: [ Sen. 1, subscore: 2.00 ]: A recombinant plasmid carrying the trp operon from Escherichia coli , which synthesizes tryptophan from chorismate , was constructed by using a broad host range plasmid vector pRK290 ; a mutant trp plasmid for tryptophan overproduction was then selected . [ Sen. 5, subscore: 2.00 ]: As expected , the amount of tryptophan biosynthesis in A lipoferum KY6 ( pMJC101 ) was increased approximately 100-fold as compared with the wild type , which led to overproduction of indole acetic acid even without addition of exogenous tryptophan . [ Sen. 3, subscore: 1.00 ]: Anthranilate synthetase is known to be the trpE gene product which plays a key role in the regulatory step in the feedback control of tryptophan biosynthesis . [ Sen. 4, subscore: 1.00 ]: The enzyme activity of the Azospirillum lipoferum KY6 carrying pMJC1 or pMJC101 was respectively 7 and 30-fold higher than that of the wild type in the presence of 10 ( -4 ) M tryptophan .
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Score: 5.00 | Title: [ Research of indole-3-acetic acid biosynthetic pathway of Klebsiella oxytoca SG-11 by HPLC and GC-MS ] | Author: LEZX Song W | Journal: Year: 2000 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub12541509 Accession (PMID): 12541509 | Abstract: The plant growth promoting bacteria are closely associated to plant .
The bacteria are used to adhering to plant rhizoplane , promoting plant growth by fixing nitrogen from atmosphere , secreting stimulating substances or producing antagonistic to plant pathogens .
It was indicated that the biological nitrogen fixation played an important role in plant growth promoting function .
In fact , it was verified recently by overall research that IAA does it .
Therefore research of IAA production and biosynthetic pathway of plant growth-promoting bacteria is much more important .
The various ways of IAA production indicated the strong or weak promoting function of bacterium to plants in general The purpose of this paper is to determine whether IAA exists in cultured medium of Klebsiella axytoca SG-11 and biosynthetic pathway of IAA , in order to opimize cultural conditions for IAA production .
Klebsiella axytoca SG-11 is a plant growth promoting bacterium , isolated from rice rhizoplane , which can fix nitrogen .
The supernatant of SG-11 cultured medium determined by HPLC showed that 47 . 4 mg/L of IAA existed in LB medium and 1 . 2 mg/L of IAA , in basal medium .
IAA in metabolite was identified by GC/MS as well .
The intermediate determination of tryptamine , indole-3-acetamide , tryptophol and indole-3-acetonitrile indirectly indicated that IAA was biosynthesized in a pathway of indole-3-pyruvic acid .
Meanwhile , tryptophol in metabolite of SG-11 was verified by GC/MS .
The direct intermediates of indole-3-pyruvic acid and indole-3-acetaldehyde in the pathway can not be determined , because both are unstable under normal condition .
As reversible conversion existed between indole-3 pyruvic aldehyde and tryptophol , the presence of tryptophol also proved the pathway of indole-3-pyruvic acid in the synthesis of IAA by Klebsiella axytoca SG-11 .
The results laid basis for further research of plant growth-promoting function of the bacterium .
| Matching Sentences: [ Sen. 10, subscore: 2.00 ]: The intermediate determination of tryptamine , indole-3-acetamide , tryptophol and indole-3-acetonitrile indirectly indicated that IAA was biosynthesized in a pathway of indole-3-pyruvic acid . [ Sen. 13, subscore: 2.00 ]: As reversible conversion existed between indole-3 pyruvic aldehyde and tryptophol , the presence of tryptophol also proved the pathway of indole-3-pyruvic acid in the synthesis of IAA by Klebsiella axytoca SG-11 . [ Sen. 11, subscore: 1.00 ]: Meanwhile , tryptophol in metabolite of SG-11 was verified by GC/MS .
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