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Score: 7.00 | Title: Rice Virescent3 and Stripe1 Encoding the Large and Small Subunits of Ribonucleotide Reductase Are Required for Chloroplast Biogenesis during Early Leaf Development .
| Author: Yoo SC Cho SH Sugimoto H Li J Kusumi K Koh HJ Iba K Paek NC | Journal: Plant Physiol Citation: V : 150 P : 388-401 Year: 2009 Type: In-Data-Review | Literature: oryza Field: abstract Doc ID: pub19297585 Accession (PMID): 19297585 | Abstract: The virescent3 ( v3 ) and stripe1 ( st1 ) mutants in rice ( Oryza sativa ) produce chlorotic leaves in a growth stage-dependent manner under field conditions .
They are temperature-conditional mutants that produce bleached leaves at a constant 20 degrees C or 30 degrees C but almost green leaves under diurnal 30 degrees C/20 degrees C conditions .
Here , we show V3 and St1 , which encode the large and small subunits of ribonucleotide reductase ( RNR ) , RNRL1 , and RNRS1 , respectively .
RNR regulates the rate of deoxyribonucleotide production for DNA synthesis and repair .
RNRL1 and RNRS1 are highly expressed in the shoot base and in young leaves , and the expression of the genes that function in plastid transcription/translation and in photosynthesis is altered in v3 and st1 mutants , indicating that a threshold activity of RNR is required for chloroplast biogenesis in developing leaves .
There are additional RNR homologs in rice , RNRL2 and RNRS2 , and eukaryotic RNRs comprise alpha ( 2 ) beta ( 2 ) heterodimers .
In yeast , RNRL1 interacts with RNRS1 ( RNRL1 : RNRS1 ) and RNRL2 : RNRS2 , but no interaction occurs between other combinations of the large and small subunits .
The interacting activities are RNRL1 : RNRS1 > RNRL1 : rnrs1 ( st1 ) > rnrl1 ( v3 ) : RNRS1 > rnrl1 ( v3 ) : rnrs1 ( st1 ) , which correlate with the degree of chlorosis for each genotype .
This suggests that missense mutations in rnrl1 ( v3 ) and rnrs1 ( st1 ) attenuate the first alphabeta dimerization .
Moreover , wild-type plants exposed to a low concentration of an RNR inhibitor , hydroxyurea , produce chlorotic leaves without growth retardation , reminiscent of v3 and st1 mutants .
We thus propose that upon insufficient activity of RNR , plastid DNA synthesis is preferentially arrested to allow nuclear genome replication in developing leaves , leading to continuous plant growth .
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Score: 4.00 | Title: Comparison of Escherichia coli ST131 pulsotypes , by epidemiologic traits , 1967-2009 .
| Author: Johnson JR Nicolas-Chanoine MH DebRoy C Castanheira M Robicsek A Hansen G Weissman S Urban C Platell J Trott D Zhanel G Clabots C Johnston BD Kuskowski MA | Journal: Emerg Infect Dis Citation: V : 18 P : 598-607 Year: 2012 Type: MEDLINE | Literature: oryza Field: abstract Doc ID: pub22469129 Accession (PMID): 22469129 | Abstract: Escherichia coli sequence type 131 ( ST131 ) , an emerging disseminated public health threat , causes multidrug-resistant extraintestinal infections .
Among 579 diverse E coli ST131 isolates from 1967-2009 , we compared pulsotypes ( >94% similar XbaI pulsed-field gel electrophoresis profiles ) by collection year , geographic origin , source , and antimicrobial drug-resistance traits .
Of 170 pulsotypes , 65 had >2 isolates and accounted for 85% of isolates .
Although extensively dispersed geographically , pulsotypes were significantly source specific ( eg , had little commonality between humans vs foods and food animals ) .
The most prevalent pulsotypes were associated with recent isolation , humans , and antimicrobial drug resistance .
Predominant pulsotype 968 was associated specifically with fluoroquinolone resistance but not with extended-spectrum beta-lactamase production or bla ( CTX-M-15 ) .
Thus , several highly successful antimicrobial drug-resistant lineages within E coli ST131 have recently emerged and diffused extensively among locales while maintaining a comparatively restricted host/source range .
Identification of factors contributing to this behavior of ST131 could help protect public health .
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Score: 3.00 | Title: Escherichia coli sequence type ST131 as an emerging fluoroquinolone-resistant uropathogen among renal transplant recipients .
| Author: Johnson JR Johnston B Clabots C Kuskowski MA Pendyala S Debroy C Nowicki B Rice J | Journal: Antimicrob Agents Chemother Citation: V : 54 P : 546-50 Year: 2010 Type: In-Process | Literature: oryza Field: abstract Doc ID: pub19917759 Accession (PMID): 19917759 | Abstract: Among 40 Escherichia coli urine isolates from renal transplant recipients ( Galveston , TX , 2003 to 2005 ) , sequence type ST131 ( O25 : H4 ) was highly prevalent ( representing 35% of isolates overall and 60% of fluoroquinolone-resistant isolates ) , virulent appearing , antimicrobial resistant ( but extended-spectrum-cephalosporin susceptible ) , and associated with black race .
Pulsotypes were diverse ; some were linked to other locales .
ST131 emerged significantly during the study period .
These findings suggest that E coli ST131 may constitute an important new multidrug-resistant threat to renal transplant recipients .
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Score: 3.00 | Title: Escherichia coli bloodstream infection after transrectal ultrasound-guided prostate biopsy : implications of fluoroquinolone-resistant sequence type 131 as a major causative pathogen .
| Author: Williamson DA Roberts SA Paterson DL Sidjabat H Silvey A Masters J Rice M Freeman JT | Journal: Clin Infect Dis Citation: V : 54 P : 1406-12 Year: 2012 Type: In-Process | Literature: oryza Field: abstract Doc ID: pub22419681 Accession (PMID): 22419681 | Abstract: BACKGROUND : Transrectal ultrasound-guided ( TRUS ) prostate biopsy is a commonly performed procedure , and fluoroquinolones are the most frequently given prophylactic antimicrobials .
In the context of increasing fluoroquinolone resistance , and the international emergence of fluoroquinolone-resistant sequence type 131 ( ST131 ) Escherichia coli , we describe a large series of E coli bacteremia after TRUS biopsy .
METHODS : All male patients admitted with community-onset ( CO ) E coli bacteremia from January 2006 through December 2010 were included .
Patient characteristics , treatment outcomes , and rates of antimicrobial resistance were compared between patients with TRUS biopsy-related bacteremia and other male patients with CO E coli bacteremia .
Molecular typing was performed on E coli isolates to determine phylogenetic group .
RESULTS : A total of 258 male patients were admitted with CO E coli bacteremia .
Of these , 47 patients ( 18% ) were admitted after TRUS biopsy .
Patients who had undergone TRUS biopsy were twice as likely to require intensive care admission ( 25% vs 12% ) and had significantly higher rates of resistance to gentamicin ( 43% ) , trimethoprim-sulphamethoxazole ( 60% ) , and ciprofloxacin ( 62% ) as well as all 3 agents in combination ( 19% ) .
Thirty-six percent of post-TRUS biopsy patients did not receive active empirical antibiotic therapy .
The ST131 clone accounted for 41% of all E coli isolates after TRUS biopsy .
CONCLUSIONS : E coli bacteremia can be a life-threatening complication of TRUS biopsy .
Infecting strains are frequently multidrug-resistant and resistant to common empirical antibiotic agents .
E coli ST131 is an important cause of sepsis after TRUS biopsy .
Further studies should evaluate colonization with fluoroquinolone-resistant E coli as a risk factor for postbiopsy sepsis .
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Score: 1.00 | Title: Escherichia coli sequence type ST131 as an emerging fluoroquinolone-resistant uropathogen among renal transplant recipients .
| Author: Johnson JR Johnston B Clabots C Kuskowski MA Pendyala S Debroy C Nowicki B Rice J | Journal: Antimicrob Agents Chemother Citation: V : 54 P : 546-50 Year: 2010 Type: In-Process | Literature: oryza Field: title Doc ID: pub19917759 Accession (PMID): 19917759 | Abstract: Among 40 Escherichia coli urine isolates from renal transplant recipients ( Galveston , TX , 2003 to 2005 ) , sequence type ST131 ( O25 : H4 ) was highly prevalent ( representing 35% of isolates overall and 60% of fluoroquinolone-resistant isolates ) , virulent appearing , antimicrobial resistant ( but extended-spectrum-cephalosporin susceptible ) , and associated with black race .
Pulsotypes were diverse ; some were linked to other locales .
ST131 emerged significantly during the study period .
These findings suggest that E coli ST131 may constitute an important new multidrug-resistant threat to renal transplant recipients .
| Supplemental links/files: reference in endnote online text related articles pubmed citation | |