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531.
532.
Md Akhlaqur Rahman Sukrat Sinha Shephali Sachan Gaurav Kumar Shailendra Kumar Singh Shanthy Sundaram 《Bioinformation》2014,10(7):449-453
Mycosporine- like amino acids (MAAs) are small (<400Da), colourless, water soluble compounds composed of cyclohexenone or
cyclohexinimine chromophere conjugated with the nitrogen substituent of amino acid or its amino alcohol. These compounds are
known for their UV- absorbing role in various organisms and seem to have evolutionary significance. The biosynthesis of MAAs is
presumed to occur via the first part of shikimate pathway. In the present work two cyanobacteria Synechocystis PCC 6803 and
Anabaena cylindrica were tested for their ability to synthesize MAAs and protein involved in the production of MAAs. It was found
that protein sequence 3-phosphoshikimate 1-carboxyvinyltransferase is involved in producing mycosporine glycine in Synechocystis
PCC 6803 and 3-dehydroquinate synthase is involved for producing shinorine in Anabaena cylindrica. Phylogenetic and
bioinformatic analysis of Mycosporine like amino acid producing protein sequence of both cyanobacterial species Synechocystis
PCC 6803 and Anabaena cylindrica provide a useful framework to understand the relationship of the different forms and how they
have evolved from a common ancestor. These products seem to be conserved but the residues are prone to variation which might
be due the fact that different cyanobacteria show different physiological process in response of Ultraviolet stress. 相似文献
533.
David L. McClure Burney A. Kieke Maria E. Sundaram Melissa D. Simpson Jennifer K. Meece Frangiscos Sifakis Robert A. Gasser Jr Edward A. Belongia 《PloS one》2014,9(7)
Background
Diagnostic testing for respiratory syncytial virus (RSV) is not routinely performed in adults. We estimated medically attended RSV seasonal incidence in a community cohort of adults ≥50 years old during four influenza seasons (2006–07 through 2009–10).Methods
Patients seeking care for acute respiratory illness (ARI) were prospectively enrolled and tested for RSV by multiplex RT-PCR. Results from enrolled patients were used to estimate projected cases among non-enrolled patients with ARI. The seasonal incidence of medically attended RSV was the sum of actual and projected cases divided by the community cohort denominator. Since each enrollment period did not include the entire RSV season, incidence estimates were adjusted to account for the statewide proportion of RSV occurring outside the study enrollment period.Results
There were 16,088 to 17,694 adults in the cohort each season and 164 RSV cases in all 4 seasons. The overall seasonal incidence of medically attended RSV was 154 episodes (95% CI, 132–180) per 10,000 persons; the incidence was highest in 2007–08 (179) and lowest in 2006–07 (110). Among persons 50–59, 60–69, and ≥70 years old, RSV incidence was 124 (95% CI, 99–156), 147 (95% CI, 110–196), and 199 (95% CI, 153–258), respectively.Conclusions
The incidence of medically attended RSV increased with age and was similar during four seasons. 相似文献534.
Lee Siew-Keah Arunkumar Sundaram K. N. S. Sirajudeen Rahimah Zakaria H. J. Singh 《Journal of physiology and biochemistry》2014,70(1):73-79
Antenatal and postnatal environments are hypothesised to influence the development of hypertension. This study investigates the synergistic effect of cross-fostering and melatonin supplementation on the development of hypertension and renal glutathione system in spontaneously hypertensive rats (SHR). In one experiment, 1-day-old male SHR pups were fostered to either SHR (shr-SHR) or Wistar-Kyoto rats, (shr-WKY). In a concurrent experiment, SHR dams were given melatonin in drinking water (10 mg/kg body weight) from day 1 of pregnancy. Immediately following delivery, 1-day-old male pups were fostered either to SHR (Mel-shr-SHR) or WKY (Mel-shr-WKY) dams receiving melatonin supplementation until weaning on day 21. Upon weaning, melatonin supplementation was continued to these pups until the age of 16 weeks. Systolic blood pressures (SBP) were recorded at the age of 4, 6, 8, 12 and 16 weeks. Renal antioxidant activities were measured. Mean SBP of shr-WKY, Mel-shr-SHR and Mel-shr-WKY was significantly lower than that in shr-SHR until the age of 8 weeks. At 12 and 16 weeks of age, mean SBP of Mel-shr-WKY was lower than those in non-treated shr-SHR and shr-WKY pups but was not significantly different from that in Mel-shr-SHR. Renal glutathione peroxidase (GPx) and glutathione S-transferase (GST) activities were significantly higher in Mel-shr-SHR and Mel-shr-WKY at 16 weeks of age. It appears that combination of cross-fostering and melatonin supplementation exerts no synergistic effect on delaying the rise in blood pressure in SHR. The elevated GPx and GST activities are likely to be due to the effect of melatonin supplementation. 相似文献
535.
536.
K. Pranathi B. C. Viraktamath C. N. Neeraja S. M. Balachandran A. S. Hariprasad P. Koteswara Rao S. R. Kulkarni P. Senguttuvel S. K. Hajira C. H. Balachiranjeevi S. Bhaskar Naik V. Abhilash M. Anila H. K. Mahadevaswamy G. Rekha M. S. Madhav P. Revathi G. Harika T. Dilip B. Kemparaju R. M. Sundaram 《Molecular breeding : new strategies in plant improvement》2016,36(3):21
WA-CMS system based rice hybrids are widely adopted in many rice growing countries, including India. Even though it is well known that the trait is controlled by mitochondria, the genes underpinning the trait remain enigmatic. In the present study, a complete genome-wide comparative sequence analysis was performed using draft mitochondrial genomes of WA-CMS and male fertile lines in a step-wise manner, progressively covering 5–10 kb every time through BLASTN tool. The sequence polymorphisms identified in different mitochondrial regions were targeted to develop two different sets of dominant PCR-based markers, one consisting of six markers targeting WA-CMS mitochondria, the other set consisting of five markers targeting male fertile mitochondria in addition to development of a set of eight co-dominant PCR-based markers targeting both the genomes. When a set of candidate genes/ORFs reported earlier to be associated with WA-CMS trait in rice were analyzed through RT-PCR of RNA isolated from immature rice florets, it was observed that the chimeric ORF, WA352 is expressed only in WA-CMS line and hybrid (i.e. genotypes containing sterile mitochondria), indicating it’s candidacy for the WA-CMS trait. Targeting the functional nucleotide polymorphism between WA-CMS and maintainer mitochondria with respect to WA352, two dominant markers, one targeting sterile and another targeting fertile mitochondria were developed. In addition, a robust, co-dominant functional marker targeting the candidate gene was also developed and validated for its utility in identification of genetic impurities in seed lots of WA-CMS lines. 相似文献
537.
538.
539.
Madhaiyan M Poonguzhali S Senthilkumar M Sundaram S Sa T 《Microbiological research》2009,164(1):114-120
The nitrogen fixing methylotrophic bacteria were isolated from the nodules of tropical legumes. Two isolates CMCJ317 and CMSA322 isolated from Crotalaria juncea and Sesbania aculeata possessing high nitrogenase activities under pure culture conditions and able to form nodules under inoculated conditions were further characterized. The biochemical characteristics revealed their close relationship with Methylobacterium nodulans type strain ORS2060. The PCR amplification of nodA and mxaF genes showed the expected 584 and 555 bp products, respectively, similar to M. nodulans ORS2060 and digestion with restriction enzymes revealed that the two isolates differed. The strains showed significantly higher nitrogenase activity and also improved nodulation and shoot nitrogen of the plants when inoculated to Macroptilum atropurpureum. CMCJ317 and CMSA322 formed nodules on C. juncea and M. atropurpureum under green house conditions and also significantly increased the nitrogen concentration in shoots. These findings show that the ability to establish symbiosis with legumes is more widespread in Methylobacterium. 相似文献
540.
Aruliah Rajasekar Balakrishnan Anandkumar Sundaram Maruthamuthu Yen-Peng Ting Pattanathu K. S. M. Rahman 《Applied microbiology and biotechnology》2010,85(4):1175-1188
Microbiologically influenced corrosion is a problem commonly encountered in facilities in the oil and gas industries. The
present study describes bacterial enumeration and identification in diesel and naphtha pipelines located in the northwest
and southwest region in India, using traditional cultivation technique and 16S rDNA gene sequencing. Phylogenetic analysis
of 16S rRNA sequences of the isolates was carried out, and the samples obtained from the diesel and naphtha-transporting pipelines
showed the occurrence of 11 bacterial species namely Serratia marcescens ACE2, Bacillus subtilis AR12, Bacillus cereus ACE4, Pseudomonas aeruginosa AI1, Klebsiella oxytoca ACP, Pseudomonas stutzeri AP2, Bacillus litoralis AN1, Bacillus sp., Bacillus pumilus AR2, Bacillus carboniphilus AR3, and Bacillus megaterium AR4. Sulfate-reducing bacteria were not detected in samples from both pipelines. The dominant bacterial species identified
in the petroleum pipeline samples were B. cereus and S. marcescens in the diesel and naphtha pipelines, respectively. Therefore, several types of bacteria may be involved in biocorrosion arising
from natural biofilms that develop in industrial facilities. In addition, localized (pitting) corrosion of the pipeline steel
in the presence of the consortia was observed by scanning electron microscopy analysis. The potential role of each species
in biofilm formation and steel corrosion is discussed. 相似文献