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1.
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The ligand field density functional theory (LFDFT) algorithm is extended to treat the electronic structure and properties of systems with three-open-shell electron configurations, exemplified in this work by the calculation of the core and semi-core 1s, 2s, and 3s one-electron excitations in compounds containing transition metal ions. The work presents a model to non-empirically resolve the multiplet energy levels arising from the three-open-shell systems of non-equivalent ns, 3d, and 4p electrons and to calculate the oscillator strengths corresponding to the electric-dipole 3d m  → ns 13d m 4p 1 transitions, with n = 1, 2, 3 and m = 0, 1, 2, …, 10 involved in the s electron excitation process. Using the concept of ligand field, the Slater-Condon integrals, the spin-orbit coupling constants, and the parameters of the ligand field potential are determined from density functional theory (DFT). Therefore, a theoretical procedure using LFDFT is established illustrating the spectroscopic details at the atomic scale that can be valuable in the analysis and characterization of the electronic spectra obtained from X-ray absorption fine structure or electron energy loss spectroscopies.  相似文献   

3.
The objective of this study was to determine the occurrence and distribution of antibiotic resistant (AR) lactic acid bacteria (LAB) in Indian poultry. LAB from poultry farm feces (n = 21) and samples from slaughter houses comprising chicken intestine (n = 46), raw meat (n = 23), and sanitary water (n = 4) were evaluated and compared with those from organic chicken (OC) collected from nearby villages. Screening studies showed 5–7 log units higher erythromycin (ER), tetracycline (TC) and vancomycin (VAN) resistant LAB from conventional poultry chicken (CC) compared to OC. Molecular characterization of isolated cultures (n = 32) with repetitive-PCR profiling and 16S rRNA gene sequencing revealed their taxonomical status as Enterococcus faecium (n = 16), Enterococcus durans (n = 2), Lactobacillus plantarum (n = 10), Lactobacillus pentosus (n = 1) and Lactobacillus salivarius (n = 3). The isolates were found to harbor erm(B), msr(C), msr(A/B), tet(M), tet(L) and tet(K) genes associated with Tn916 and Tn917 family transposons. Expression studies through real-time PCR revealed antibiotic-induced expression of the identified AR genes. In vitro and in vivo conjugational studies revealed transfer of ER and TC resistant (ERR and TCR) genes with transfer frequencies of 10?7 and 10?4 transconjugants recipient?1, respectively. Although no known VAN resistance (VANR) genes were detected, high phenotypic resistance was observed and was transferable to the recipient. From a public health point of view, this study reports Indian poultry as a major source of high levels of AR bacteria contaminating the food chain and the environment. Thus, urgent and determined strategies are needed to control the spread of multiple AR bacteria.  相似文献   

4.
This study investigated the genetic association of three single nucleotide polymorphisms(SNPs; rs10483727, rs33912345, and rs146737847) at the SIX1-SIX6 locus with primary open angle glaucoma(POAG) in the Chinese population. A total of 866 subjects with POAG(685 high-tension glaucoma(HTG) and 181 normal-tension glaucoma(NTG)) and 266 control individuals were included. Significant genetic association was identified for rs10483727 in HTG(P=0.02; odds ratio(OR)=1.31), NTG(P=7.41×10~(-6); OR=2.71), and POAG(i.e., HTG and NTG combined; P=0.001; OR=1.44). rs33912345 was also significantly associated with HTG(P=0.008; OR=1.36), NTG(P=2.72×10~(-6); OR=2.27), and POAG(P=3.84×10~(-4); OR=1.49). The rare SIX6 mutation, rs146737847, was not found in the subjects enrolled in this study. Stratification by patient age identified that both rs10483727 and rs33912345 were significantly associated with NTG in patients aged above 40 years(P=2.08×10~(-5); OR=2.28), whereas in patients aged between 20–40 years, rs33912345 was significantly associated with NTG(P=0.017; OR=2.06). In HTG, the genetic associations for both rs10483727 and rs33912345 were significant in patients aged between 20–40 years(P=0.006; OR=1.56) but not in those aged above 40 years(P=0.118, OR=1.21 and P=0.042, OR=1.29, respectively). This study replicated the association of POAG with two SNPs at the SIX1-SIX6 locus and demonstrated that SNPs, rs10483727 and rs33912345, are significantly associated with POAG, especially with NTG in patients aged above 40 years.  相似文献   

5.
Odonata have been widely used as indicators for the biomonitoring of terrestrial and aquatic habitats due to their sensitivity to environmental impacts. We aimed to determine whether the larval or adult phases of these insects were the best predictors of variation in habitat parameters and the loss of environmental integrity. Specimens were collected during three seasons (dry, rainy, and ebb) from 12 points in the Suiá-missu River basin, at the headwaters of the Xingu River in Mato Grosso, Brazil. The Protest analysis indicated a high degree of congruence between the assemblages of larvae and adults in streams with varying degrees of habitat integrity (R = 0.832, p < 0.001, m 2 = 0.307). When the congruence with environmental factors was analyzed, a significant association was found only for the larval phase (R = 0.318, p = 0.03, m 2 = 0.888). When the suborders were analyzed separately, congruence was confirmed for anisopteran adults (R = 0.338, p = 0.031, m 2 = 0.885) and larvae (R = 0.417, p = 0.003, m 2 = 0.826) and for the zygopteran adults (R = 0.345, p = 0.027, m 2 = 0.881) and larvae (R = 0.405, p = 0.011, m 2 = 0.836). These results indicate that both larvae and adults respond systematically to environmental impacts. We suggest that either life phase can be used for biomonitoring, given their effectiveness for the interpretation of disturbance in terrestrial and aquatic habitats. These findings further reinforce the effectiveness of this insect order for the detection of modifications to the environment, showing that they are good indicators of environmental conditions.  相似文献   

6.
Sublethal concentrations of chemical insecticides may cause changes in some behavioral characteristics of natural enemies such as functional responses. The residual effect of three synthetic insecticides including deltamethrin, fenvalerate and azadirachtin were studied on functional response of Habrobracon hebetor Say to Ephestia kuehniella Zeller larvae. Seven host densities (2, 4, 8, 16, 32, 64 and 96) were used during a 24 h period. The resulting data were appropriately fit to Type II functional response models in all treatments: (1) control (0.0916 h?1; and T h  = 0.2011 h); (2) deltamethrin (a = 0.0839 h?1; and T h  = 0.3560 h); (3) fenvalerate (a = 0.0808 h?1 and T h  = 0.3623 h); and (4) azadirachtin (a = 0.0900 h?1 and T h  = 0.2042 h). Maximum theoretical parasitism rate (T/T h ) was 119.34 estimated for control wasps. There was no significant difference between the values of attack rates (a and a + D a ) in all treatments while the handling time was statistically affected in female wasps treated with fenvalerate. Our findings will be useful in safe application of these insecticides in pest management programmes.  相似文献   

7.
Adenine phosphoribosyltransferase (APRT) from a thermophilic bacterial strain Thermus thermophilus НВ27 (TthHB27APRT) belongs to the family of type I phosphoribosyltransferases and catalyzes the magnesium-dependent transfer of 5'-phosphoribosyl group from 5'-phosphoribosylpyrophosphate to N9 adenine nitrogen with formation of adenosine-5'-monophosphate and pyrophosphate. The crystals of the recombinant enzyme suitable for X-ray study were grown in a capillary using the counter-diffusion technique. Crystals with unit-cell parameters α = 69.860 Å, b = 82.160 Å, c = 91.390 Å, α = 90.00°, β = 102.58°, and γ = 90.00° belong to the space group Р21 and contain six enzyme monomers in the asymmetric unit. The set of X-ray data from grown crystals was collected on a Spring-8 synchrotron radiation facility (Japan) and three-dimensional structure of the enzyme was solved at 2.7-Å resolution by molecular replacement method using the BALBES software. The polypeptide fold in the enzyme monomer and the structure of biologically active dimer were described. Based on the comparison with structures of homologous APRTs from a thermophilic strain ThtHB8 and Homo sapiens, positions of active site and a number of functionally important amino acids were located.  相似文献   

8.
Sixteen yeast isolates identified as belonging to the genus Sugiyamaella were studied in relation to D-xylose fermentation, xylitol production, and xylanase activities. The yeasts were recovered from rotting wood and sugarcane bagasse samples in different Brazilian regions. Sequence analyses of the internal transcribed spacer (ITS) region and the D1/D2 domains of large subunit rRNA gene showed that these isolates belong to seven new species. The species are described here as Sugiyamaella ayubii f.a., sp. nov. (UFMG-CM-Y607T = CBS 14108T), Sugiyamaella bahiana f.a., sp. nov. (UFMG-CM-Y304T = CBS 13474T), Sugiyamaella bonitensis f.a., sp. nov. (UFMG-CM-Y608T = CBS 14270T), Sugiyamaella carassensis f.a., sp. nov. (UFMG-CM-Y606T = CBS 14107T), Sugiyamaella ligni f.a., sp. nov. (UFMG-CM-Y295T = CBS 13482T), Sugiyamaella valenteae f.a., sp. nov. (UFMG-CM-Y609T = CBS 14109T) and Sugiyamaella xylolytica f.a., sp. nov. (UFMG-CM-Y348T = CBS 13493T). Strains of the described species S. boreocaroliniensis, S. lignohabitans, S. novakii and S. xylanicola, isolated from rotting wood of Brazilian ecosystems, were also compared for traits relevant to xylose metabolism. S. valenteae sp. nov., S. xylolytica sp. nov., S. bahiana sp. nov., S. bonitensis sp. nov., S. boreocarolinensis, S. lignohabitans and S. xylanicola were able to ferment d-xylose to ethanol. Xylitol production was observed for all Sugiyamaella species studied, except for S. ayubii sp. nov. All species studied showed xylanolytic activity, with S. xylanicola, S. lignohabitans and S. valenteae sp. nov. having the highest values. Our results suggest these Sugiyamaella species have good potential for biotechnological applications.  相似文献   

9.
We explored the relationships between perturbation-driven population decline and genetic/genotypic structure in the clonal seagrass Posidonia oceanica, subject to intensive meadow regression around four Mediterranean fish-farms, using seven specific microsatellites. Two meadows were randomly sampled (40 shoots) within 1,600 m2 at each site: the “impacted” station, 5–200 m from fish cages, and the “control” station, around 1,000 m downstream further away (considered a proxy of the pre-impact genetic structure at the site). Clonal richness (R), Simpson genotypic diversity (D*) and clonal sub-range (CR) were highly variable among sites. Nevertheless, the maximum distance at which clonal dispersal was detected, indicated by CR, was higher at impacted stations than at the respective control station (paired t-test: P < 0.05, N = 4). The mean number of alleles (Â) and the presence of rare alleles ( r) decreased at impacted stations (paired t-test: P < 0.05, and P < 0.02, respectively, N = 4). At a given perturbation level (quantified by the organic and nutrient loads), shoot mortality at the impacted stations significantly decreased with CR at control stations (R = 0.86, P < 0.05). Seagrass mortality also increased with  (R = 0.81, P < 0.10), R (R = 0.96, P < 0.05) and D* (R = 0.99, P < 0.01) at the control stations, probably because of the negative correlation between those parameters and CR. Therefore, the effects of clonal size structure on meadow resistance could play an important role on meadow survival. Large genotypes of P. oceanica meadows thus seem to resist better to fish farm-derived impacts than little ones. Clonal integration, foraging advantage or other size-related fitness traits could account for this effect.  相似文献   

10.
Gender dysphoria is commonly thought to arise from discrepant cerebral and genital sexual differentiation. Increasing evidence supports the idea of genetic vulnerability. The purpose of this paper was to investigate whether the polymorphism CYP17-MspA1 rs743572 is associated with gender dysphoria. Fragments that included the rs743572 polymorphism were PCR amplified and digested with MspA1 in 317 MtFs, 223 FtMs, 358 control men and 264 control women. The allele/genotype frequencies were compared between groups, with the 1000 Genomes Data Base and with international literature. Allele and genotype frequencies did not differ significantly between the FtM and female control groups (χ2 = 0.631; p = 0.43 and χ2 = 2.767; p = 0.25), or between the MtF and male control groups (χ2 = 0.105; p = 0.74 and χ2 = 0.789; p = 0.67). A2 frequency was higher in the FtM (0.43) than the female control group (0.41), male control group (0.40), or MtF group (0.39), but this difference did not reach statistical significance. Genotype frequencies did not differ significantly between groups (p = 0.66), between genotypes (p = 0.4) or between sexes (p = 0.66). Our data contradict previous findings about the CYP17-MspA1 rs743572 polymorphism and gender dysphoria and concur with the 1000 Genomes Data Base, which shows that the allele frequencies vary between countries and ethnicities but not between sexes. Our data do not support a hypothetical involvement of the rs743572 polymorphism in the genetic basis of gender dysphoria.  相似文献   

11.
Effects of oxygen transfer on recombinant protein production by Pichia pastoris under glyceraldehyde-3-phosphate dehydrogenase promoter were investigated. Recombinant glucose isomerase was chosen as the model protein. Two groups of oxygen transfer strategies were applied, one of which was based on constant oxygen transfer rate where aeration rate was Q O/V = 3 and 10 vvm, and agitation rate was N = 900 min?1; while the other one was based on constant dissolved oxygen concentrations, C DO = 5, 10, 15, 20 and 40 % in the fermentation broth, by using predetermined exponential glucose feeding with μ o = 0.15 h?1. The highest cell concentration was obtained as 44 g L?1 at t = 9 h of the glucose fed-batch phase at C DO = 20 % operation while the highest volumetric and specific enzyme activities were obtained as 4440 U L?1 and 126 U g?1 cell, respectively at C DO = 15 % operation. Investigation of specific enzyme activities revealed that keeping C DO at 15 % was more advantageous with an expense of relatively higher by-product formation and lower specific cell growth rate. For this strategy, the highest oxygen transfer coefficient and oxygen uptake rate were K L a = 0.045 s?1 and OUR = 8.91 mmol m?3 s?1, respectively.  相似文献   

12.

Introduction

The Elongator complex, comprising six subunits (Elp1p-Elp6p), is required for formation of 5-carbamoylmethyl (ncm5) and 5-methoxycarbonylmethyl (mcm5) side chains on wobble uridines in 11 out of 42 tRNA species in Saccharomyces cerevisiae. Loss of these side chains reduces the efficiency of tRNA decoding during translation, resulting in pleiotropic phenotypes. Overexpression of hypomodified \( {\text {tRNA}_{{\rm s^{2} {\rm UUU}}}^{{\rm Lys}} , {\rm tRNA}_{{\rm s^{2} {\rm UUG}}}^{{\rm Gln }} \;{\rm and}\;{\rm tRNA}_{{\rm s^{2} {\rm UUC}}}^{{\rm Glu}}} \), which in wild-type strains are modified with mcm5s2U, partially suppress phenotypes of an elp3Δ strain.

Objectives

To identify metabolic alterations in an elp3Δ strain and elucidate whether these metabolic alterations are suppressed by overexpression of hypomodified \( {\text {tRNA}_{{\rm s^{2} {\rm UUU}}}^{{\rm Lys}} , {\rm tRNA}_{{\rm s^{2} {\rm UUG}}}^{{\rm Gln }} \;{\rm and}\;{\rm tRNA}_{{\rm s^{2} {\rm UUC}}}^{{\rm Glu}}} \).

Method

Metabolic profiles were obtained using untargeted GC-TOF-MS of a temperature-sensitive elp3Δ strain carrying either an empty low-copy vector, an empty high-copy vector, a low-copy vector harboring the wild-type ELP3 gene, or a high-copy vector overexpressing \( {\text {tRNA}_{{\rm s^{2} {\rm UUU}}}^{{\rm Lys}} , {\rm tRNA}_{{\rm s^{2} {\rm UUG}}}^{{\rm Gln }} \;{\rm and}\;{\rm tRNA}_{{\rm s^{2} {\rm UUC}}}^{{\rm Glu}}} \). The temperature sensitive elp3Δ strain derivatives were cultivated at permissive (30 °C) or semi-permissive (34 °C) growth conditions.

Results

Culturing an elp3Δ strain at 30 or 34 °C resulted in altered metabolism of 36 and 46 %, respectively, of all metabolites detected when compared to an elp3Δ strain carrying the wild-type ELP3 gene. Overexpression of hypomodified \( {\text {tRNA}_{{\rm s^{2} {\rm UUU}}}^{{\rm Lys}} , {\rm tRNA}_{{\rm s^{2} {\rm UUG}}}^{{\rm Gln }} \;{\rm and}\;{\rm tRNA}_{{\rm s^{2} {\rm UUC}}}^{{\rm Glu}}} \) suppressed a subset of the metabolic alterations observed in the elp3Δ strain.

Conclusion

Our results suggest that the presence of ncm5- and mcm5-side chains on wobble uridines in tRNA are important for metabolic homeostasis.
  相似文献   

13.
In this study, fungemia cases from four tertiary hospitals located in Shanghai and Anhui province in China from March 2012 to December 2013 were enrolled to investigate clinical features, species distribution, antifungal susceptibility and strain relatedness. During the study period, 137 non-duplicate cases and their corresponding isolates were collected. Six different genera of fungi were identified, of which Candida spp. were the most common (126/137, 91.97 %), with C. albicans predominating (48/137, 35.03 %). The non-Candida fungi rate reached 8.03 % (11/137), and Pichia spp. was the most common (5/137, 3.65 %). Compared with C. albicans, non-C. albicans fungi-associated fungemia was more likely in younger (p = 0.004) and male patients (χ 2 = 6.2618, p = 0.0123) and patients from ICUs (χ 2 = 6.3783, p = 0.0116). Overall, the susceptible/WT rates of common Candida spp. to fluconazole, itraconazole, voriconazole, flucytosine, amphotericin B and caspofungin were 74.63, 92.31, 93.16, 96.58, 100 and 95.69 %, respectively. C. tropicalis and C. guilliermondii had a low susceptibility to fluconazole: 79.95 and 77.78 %, respectively. No isolates were resistant/WT to caspofungin, but C. parapsilosis and C. guilliermondii had high MIC90 values; 1 and 2 mg/L, respectively. In terms of genotyping, MLST was taken for C. glabrata and C. tropicalis, while microsatellite marker analysis was used for C. albicans and C. parapsilosis. C. glabrata was predominantly clone ST7, accounting for 75 %, while the other isolates showed genetic diversity. Considering the increased proportion of non-C. albicans fungi and the presence of endemic clones of C. glabrata, it is essential to undertake additional surveillance of fungemia.  相似文献   

14.
The aims of the present study were to develop a parameterization of a one-year-long observed PAR time-series, apply the PAR parameterization in a primary production relation, and compare calculated and observed time-series of primary production. The PAR parameterization was applied in the generally used relation for the primary production (P d): P d = a(BI 0 Z 0) + b with observed photic depth (Z 0) and Chl-a concentrations (B). It was tested whether the PAR parameterization in combination with this simple relation for primary production was able to describe the actual measured primary production. The study is based on a one year long time-series of PAR, CTD-casts (n = 45), and primary production measurements (n = 24) from Århus Bay (56°09′ N; 10°20′ E), south west Kattegat. Results showed a high and positive correlation between observed and calculated primary production in the bay, as based on the present PAR parameterization combined with the simple primary production relation. The developed PAR parameterization, which calculates total daily surface irradiance per day (M photons m?2 d?1), can be applied in any ecological application taking into account that it was developed for the latitude of 56° N.  相似文献   

15.
Triticum timopheevii (2n = 4x = 28, GGAtAt) is a tetraploid wheat formerly cultivated in western Georgia. The natural allopolyploid Triticum zhukovskyi is a hexaploid taxon originated from hybridization of T. timopheevii with cultivated einkorn T. monococcum (2n = 2x = 14, AmAm). Karyotypically T. timopheevii and T. zhukovskyi differ from other tetraploid and hexaploid wheats and were assigned to the section Timopheevii of the genus Triticum L. Triticum timopheevii and T. zhukovskyi are resistant to many fungal diseases and therefore could potentially be utilized for wheat improvement. We were aiming to precisely identify all T. timopheevii chromosomes and to trace the evolution of T. zhukovskyi. For this, we developed a set of molecular cytogenetic landmarks based on eleven DNA probes. Each chromosome can now be characterized by two to eight probes. The pTa-535 sequence allows the identification of all At-genome chromosomes, whereas G-genome and some At-genome chromosomes can be identified using (GAA/CTT) n and pSc119.2 probes. The probes pAesp_SAT86, pAs1, Spelt-1, Spelt-52 and 5S and 45S rDNA can be applied as additional markers to discriminate particular chromosomes or chromosomal regions. The distribution of (GAA/CTT) n , pTa-535 and pSc119.2 DNA probes on T. timopheevii chromosomes is distinct from other tetraploid wheats and can therefore be used to track individual chromosomes in introgression programs. Our study confirms the origin of T. zhukovskyi from hybridization of T. timopheevii with T. monococcum; however, we show that the emergence was accompanied by changes involving mostly At-genome chromosomes. This may be due to the presence of two closely related A-genomes in the T. zhukovskyi karyotype.  相似文献   

16.
The aim of this study is to determine the feasibility of Fourier transform infrared (FT-IR) spectroscopy for simultaneous determination of saponin contents in different soybean cultivars. In cross validation between predicted content of saponin by PLS regression modeling from FT-IR spectra and measured content by HPLC, total saponin contents were predicted with good accuracy (R 2 ≥ 0.71). In external validation, saponin group Ab (R 2 = 0.88), saponin DDMP-group βg (R 2 = 0.85), total saponin group B (R 2 = 0.88), and total saponin content (R 2 = 0.87) were predicted with good accuracy, while prediction for saponin group Aa (R 2 = 0.58), saponin group Bb′ (R 2 = 0.58), and total saponin group A (R 2 = 0.25) had relatively lower accuracy. Considering these results, we suggest that the PLS prediction system for saponin contents using FT-IR analysis could be applied as a novel screening tool for high yielding lines in soybean breeding.  相似文献   

17.
The present study was designed to synthesize the bioactive molecule 2,2-bis(2,4-dinitrophenyl)-2-(phosphonatomethylamino)acetate (1), having excellent applications in the field of plant protection as a herbicide. Structure of newly synthesized molecule 1 was confirmed by using the elemental analysis, mass spectrometric, NMR, UV-visible, and FTIR spectroscopic techniques. To obtain better structural insights of molecule 1, 3D molecular modeling was performed using the GAMESS programme. Microbial activities of 1 were checked against the pathogenic strains Aspergillus fumigatus (NCIM 902) and Salmonella typhimurium (NCIM 2501). Molecule 1 has shown excellent activities against fungal strain A. fumigates (35 μg/l) and bacterial strain S. typhimurium (25 μg/l). To check the medicinal significance of molecule 1, interactions with bovine serum albumin (BSA) protein were checked. The calculated value of binding constant of molecule 1–BSA complex was 1.4 × 106 M?1, which were similar to most effective drugs like salicylic acid. More significantly, as compared to herbicide glyphosate, molecule 1 has exhibited excellent herbicidal activities, in pre- and post-experiments on three weeds; barnyard grass (Echinochloa Crus), red spranglitop (Leptochloa filiformis), and yellow nuts (Cyperus Esculenfus). Further, effects of molecule 1 on plant growth-promoting rhizobacterial (PGPR) strains were checked. More interestingly, as compared to glyphosate, molecule 1 has shown least adverse effects on soil PGPR strains including the Rhizobium leguminosarum (NCIM 2749), Pseudomonas fluorescens (NCIM 5096), and Pseudomonas putida (NCIM 2847).  相似文献   

18.
19.
Drosophila incompta belongs to the flavopilosa group of Drosophila, and has a restricted ecology, being adapted to flowers of Cestrum as feeding and oviposition sites. We sequenced, assembled, and characterized the complete mitochondrial genome (mtDNA) of D. incompta. In addition, we performed phylogenomic and polymorphism analyses to assess evolutionary diversification of this species. Our results suggest that this genome is syntenic with the other published mtDNA of Drosophila. This molecule contains 15,641 bp and encompasses two rRNA, 22 tRNA and 13 protein-coding genes. Regarding nucleotide composition, we found a high A?T bias (76.6 %). The recovered phylogenies indicate D. incompta in the virilisrepleta radiation, as sister to the virilis or repleta groups. The most interesting result is the high degree of polymorphism found throughout the D. incompta mitogenome, revealing pronounced intrapopulational variation. Furthermore, intraspecific nucleotide diversity levels varied between different regions of the genome, thus allowing the use of different mitochondrial molecular markers for analysis of population structure of this species.  相似文献   

20.
We report the successful high-yield expression of Candida utilis uricase in Escherichia coli and the establishment of an efficient three-step protein purification protocol. The purity of the recombinant protein, which was confirmed to be C. utilis uricase by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometer analysis, was >98% and the specific activity was 38.4 IU/mg. Crystals of C. utilis uricase were grown at 18°C using 25% polyethylene glycol 3350 as precipitant. Diffraction by the crystals extends to 1.93 Å resolution, and the crystals belong to the space group P212121 with unit cell parameters a?=?69.16 Å, b?=?139.31 Å, c?=?256.33 Å, and α?=?β?=?γ?=?90°. The crystal structure of C. utilis uricase shares a high similarity with other reported structures of the homologous uricases from other species in protein database, demonstrating that the three-dimensional structure of the protein defines critically to the catalytic activities.  相似文献   

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