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11.
The N-terminal extension of rusticyanin is a unique structural feature of this protein in the cupredoxin family and has been speculated to be responsible for the extreme acid stability of the protein. We have removed the 35 residues from the N-terminus and show that the resulting -35 mutant is insoluble in aqueous media above pH 5.0 and exists primarily in a hexameric form at lower pHs. Synchrotron radiation circular dichroism (SRCD) and solution X-ray scattering data indicate that much of the beta-sheet structure is retained in acidic solution and indeed there is a small but significant increase in the beta-sheet contribution. We suggest this to be a result of beta-sheet formation between the monomer interfaces. The mutant does not bind copper. These results provide evidence that the unique N-terminus of rusticyanin is not responsible for the acid stability of the hydrophobic beta-barrel core of the protein. 相似文献
12.
Subramanian S Madgula VM George R Mishra RK Pandit MW Kumar CS Singh L 《Genome biology》2002,3(12):preprint00-13
MRD is a database system to access the microsatellite repeats information of genomes such as archea, eubacteria, and other eukaryotic genomes whose sequence information is available in public domains. MRD stores information about simple tandemly repeated k-mer sequences where k= 1 to 6, i.e. monomer to hexamer. The web interface allows the users to search for the repeat of their interest and to know about the association of the repeat with genes and genomic regions in the specific organism. The data contains the abundance and distribution of microsatellites in the coding and non-coding regions of the genome. The exact location of repeats with respect to genomic regions of interest (such as UTR, exon, intron or intergenic regions) whichever is applicable to organism is highlighted. MRD is available on the World Wide Web at and/or . The database is designed as an open-ended system to accommodate the microsatellite repeats information of other genomes whose complete sequences will be available in future through public domain. 相似文献
13.
Deepa Selvi Rani Perundurai S. Dhandapany Pratibha Nallari Periyasamy Govindaraj Lalji Singh Kumarasamy Thangaraj 《Mitochondrion》2010,10(2):166-173
Mutations in PTPN11 gene was responsible for ~50% of the Noonan syndrome (NS), however, we did not find any mutation in PTPN11 in any of seven NS patients analysed. Whereas, the complete mtDNA sequencing revealed 146 mutations, of which five, including one heteroplasmic (A11144R; Thr → Ala) non-synonymous mutation, were novel and exclusively observed in NS patients. Interestingly all the seven probands and their maternal relatives were clustered under a major haplogroup R and its novel sub-haplogroups (R7b1b, R30a1, R30c, T2b7, U9a1) exclusive in NS, therefore we strongly suggest that these haplogroups may influence NS in South Indian populations. 相似文献
14.
Martin Hucík Marek Bučko Peter Gemeiner Vladimír Štefuca Alica Vikartovská Marko D. Mihovilovič Florian Rudroff Naseem Iqbal Dušan ChorvátJr. Igor Lacík 《Biotechnology letters》2010,32(5):675-680
Recombinant Escherichia coli cells, over-expressing cyclopentanone monooxygenase activity, were immobilized in polyelectrolyte complex capsules, made
of sodium alginate, cellulose sulfate, poly(methylene-co-guanidine), CaCl2 and NaCl. More than 90% of the cell viability was preserved during the encapsulation process. Moreover, the initial enzyme
activity was fully maintained within encapsulated cells while it halved in free cells. Both encapsulated and free cells reached
the end point of the Baeyer–Villiger biooxidation of 8-oxabicyclo[3.2.1]oct-6-en-3-one to 4,9-dioxabicyclo[4.2.1]non-7-en-3-one
at the same time (48 h). Similarly, the enantiomeric excess above 94% was identical for encapsulated and free cells. 相似文献
15.
The results here are the first demonstration of a physiological agonist opening Ca2+ channels in bacteria. Bacteria in the gut ferment glucose and other substrates, producing alcohols, diols, ketones and acids, that play a key role in lactose intolerance, through the activation of Ca2+ and other ion channels in host cells and neighbouring bacteria. Here we show butane 2,3-diol (5-200mM; half maximum 25mM) activates Ca2+ transients in E. coli, monitored by aequorin. Ca2+-transient magnitude depended on external Ca2+ (0.1-10mM). meso-Butane 2,3-diol was approximately twice as potent as 2R,3R (-) and 2S,3S (+) butane 2,3-diol. There were no detectable effects on cytosolic free Ca2+ of butane 1,3-diol, butane 1,4-diol and ethylene glycol. The glycerol fermentation product propane 1,3-diol only induced significant Ca2+ transients in 10mM external Ca2. Ca2+ butane 2,3-diol Ca2+ transients were due to activation of Ca2+ influx, followed by activation of Ca2+ efflux. The effect of butane 2,3-diol was abolished by La3+, and markedly reduced as a function of growth phase. These results were consistent with butane 2,3-diol activating a novel La3+-sensitive Ca2+ channel. They have important implications for the role of butane 2,3-diol and Ca2+ in bacterial-host cell signalling. 相似文献
16.
Zerjal T Pandya A Thangaraj K Ling EY Kearley J Bertoneri S Paracchini S Singh L Tyler-Smith C 《Human genetics》2007,121(1):137-144
The caste system has persisted in Indian Hindu society for around 3,500 years. Like the Y chromosome, caste is defined at
birth, and males cannot change their caste. In order to investigate the genetic consequences of this system, we have analysed
male-lineage variation in a sample of 227 Indian men of known caste, 141 from the Jaunpur district of Uttar Pradesh and 86
from the rest of India. We typed 131 Y-chromosomal binary markers and 16 microsatellites. We find striking evidence for male
substructure: in particular, Brahmins and Kshatriyas (but not other castes) from Jaunpur each show low diversity and the predominance
of a single distinct cluster of haplotypes. These findings confirm the genetic isolation and drift within the Jaunpur upper
castes, which are likely to result from founder effects and social factors. In the other castes, there may be either larger
effective population sizes, or less strict isolation, or both.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.
Tatiana Zerjal and Arpita Pandya contributed equally to this work. 相似文献
17.
Funk SM Verma SK Larson G Prasad K Singh L Narayan G Fa JE 《Molecular phylogenetics and evolution》2007,45(2):427-436
The pygmy hog, Sus salvanius, the smallest and rarest extant suid was first described as the only member of the genus Porcula. It is currently regarded as member of the genus Sus and a sister taxon of the domestic pig/Eurasian wild boar (Sus scrofa). Phylogenetic analyses of 2316 bp from three mtDNA loci (control-region, cytochrome b, 16S) by Bayesian inference and statistical testing of alternative phylogenetic hypotheses all support the original classification of the pygmy hog as a unique genus. Thus, we propose that the species name Porcula salvania should be resurrected. The reclassification will heighten awareness of the need for the future protection and survival of this unique species. 相似文献
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20.
Roberts AC Reichl J Song MY Dearinger AD Moridzadeh N Lu ED Pearce K Esdin J Glanzman DL 《PloS one》2011,6(12):e29132
The zebrafish larva has been a valuable model system for genetic and molecular studies of development. More recently, biologists have begun to exploit the surprisingly rich behavioral repertoire of zebrafish larvae to investigate behavior. One prominent behavior exhibited by zebrafish early in development is a rapid escape reflex (the C-start). This reflex is mediated by a relatively simple neural circuit, and is therefore an attractive model behavior for neurobiological investigations of simple forms of learning and memory. Here, we describe two forms of short-lived habituation of the C-start in response to brief pulses of auditory stimuli. A rapid form, persisting for ≥1 min but <15 min, was induced by 120 pulses delivered at 0.5-2.0 Hz. A more extended form (termed "short-term habituation" here), which persisted for ≥25 min but <1 h, was induced by spaced training. The spaced training consisted of 10 blocks of auditory pulses delivered at 1 Hz (5 min interblock interval, 900 pulses per block). We found that these two temporally distinguishable forms of habituation are mediated by different cellular mechanisms. The short-term form depends on activation of N-methyl-d-aspartate receptors (NMDARs), whereas the rapid form does not. 相似文献