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991.
R. D’Anastasio J. Viciano M. Di Nicola D.T. Cesana M. Sciubba M. Del Cimmuto A. Paolucci A. Fazio L. Capasso 《HOMO》2014
Recent forensic studies have shown that the hyoid bone is a sexually dimorphic element of the human skeleton. Given the advanced techniques of collecting human remains in archeological and forensic contexts, the recovery of hyoid bones is now more frequent in skeletal samples. For that reason the authors propose a new method for estimating sex based on hyoid bodies from archeological sites. 相似文献
992.
Di Gioia D Luziatelli F Negroni A Ficca AG Fava F Ruzzi M 《Journal of biotechnology》2010,156(4):309-316
Vanillin is one of the most important flavors in the food industry and there is great interest in its production through biotechnological processes starting from natural substrates such as ferulic acid. Among bacteria, recombinant Escherichia coli strains are the most efficient vanillin producers, whereas Pseudomonas spp. strains, although possessing a broader metabolic versatility, rapidly metabolize various phenolic compounds including vanillin. In order to develop a robust Pseudomonas strain that can produce vanillin in high yields and at high productivity, the vanillin dehydrogenase (vdh)-encoding gene of Pseudomonas fluorescens BF13 strain was inactivated via targeted mutagenesis. The results demonstrated that engineered derivatives of strain BF13 accumulate vanillin if inactivation of vdh is associated with concurrent expression of structural genes for feruloyl-CoA synthetase (fcs) and hydratase/aldolase (ech) from a low-copy plasmid. The conversion of ferulic acid to vanillin was enhanced by optimization of growth conditions, growth phase and parameters of the bioconversion process. The developed strain produced up to 8.41 mM vanillin, which is the highest final titer of vanillin produced by a Pseudomonas strain to date and opens new perspectives in the use of bacterial biocatalysts for biotechnological production of vanillin from agro-industrial wastes which contain ferulic acid. 相似文献
993.
A. Palamidessi I. Testa E. Frittoli S. Barozzi M. Garrè D. Mazza P. P. Di Fiore A. Diaspro G. Scita Mario Faretta 《European biophysics journal : EBJ》2010,39(6):947-957
The dissection of the molecular circuitries at the base of cell life and the identification of their abnormal transformation
during carcinogenesis rely on the characterization of biological phenotypes generated by targeted overexpression or deletion
of gene products through genetic manipulation. Fluorescence microscopy provides a wide variety of tools to monitor cell life
with minimal perturbations. The observation of living cells requires the selection of a correct balance between temporal,
spatial and “statistical” resolution according to the process to be analyzed. In the following paper ad hoc developed optical
tools for dynamical tracking from cellular to molecular resolution will be presented. Particular emphasis will be devoted
to discuss how to exploit light–matter interaction to selectively target specific molecular species, understanding the relationships
between their intracellular compartmentalization and function. 相似文献
994.
Yeasts isolated from olive mill wastewaters from southern Italy: technological characterization and potential use for phenol removal 总被引:1,自引:0,他引:1
Milena Sinigaglia Nilde Di Benedetto Antonio Bevilacqua Maria Rosaria Corbo Angela Capece Patrizia Romano 《Applied microbiology and biotechnology》2010,87(6):2345-2354
Olive mill wastewater (OMW) samples from two traditional varieties (Peranzana and Ogliarola Garganica) of Apulian region (southern
Italy) and produced through continuous and traditional methods were microbiologically and chemically examined; thus, 104 yeasts
were isolated and selected for further analyses. The strains were identified as Candida boidinii, Pichia holstii, Pichia membranifaciens, and Saccharomyces cerevisiae and analyzed to assess their suitability to metabolize phenols. Based on phenol metabolism, 27 strains were selected and
inoculated into OMW aliquots to determine their ability to reduce phenols in vivo; then, five strains (identified with the
codes 682—C. boidinii and 625, 642, 647, and 941—P. holstii) were used as a cocktail in wastewaters for a final validation step. In this last experiment, the effects of the temperature
(10–30°C) and (NH4)2SO4 (0.0–6.0 g l−1) were studied through a central composite design approach, and the results highlighted that the cocktail was able to reduce
phenols by 40% at 10°C with 6.0 g l−1 of (NH4)2SO4 added. 相似文献
995.
996.
997.
Huan Wang Na Huo Feifei Li Shanmin Fu Yang Xue Ting Yang Xuan Wen Yin Ding Xiaohong Duan 《Molecular and cellular biochemistry》2010,339(1-2):191-199
PHR protein family consists of C. elegan Rpm-1/Drosophila Highwire/Zebrafish Esrom/Mouse Phr-1/Human Pam. Esrom is required for correct neurites exiting the paused state at intermediate targets as well as pteridine synthesis. This study reports the identification and characterization of two novel Esrom splice variants, named splice variants 2 (splicing out 5′ 24 bp of exon 17) and 3 (splicing out 5′ 24 bp of exons 17 and 18). Polypeptides encoded by 5′ 24 bp of exons 17 and 18 are part of basic amino-acid-rich region inside Esrom RCC1-like domain (RLD). These two splice variants maintain the whole protein reading frame and alternative exons usage patterns are conserved with mammal. At different developmental stages and adult zebrafish tissues, abundances of these splice variants are different. Importantly, by yeast two-hybrid screen and confocal colocalization analysis, it was found that alternative splicing of exon 18 regulates Esrom RLD interaction with kinesin family member 22 and G protein beta-subunit 1. Taken together, these results suggest that Esrom RLD functions are regulated by alternative splicing at temporal and spatial-specific manner. 相似文献
998.
Jin Ming Di Jun Pang Qi Peng Sun Yan Zhang You Qiang Fang Xiao Pen Liu Jian Hua Zhou Xing Xing Ruan Xin Gao 《Molecular biology reports》2010,37(4):1849-1855
CpG-oligonucleotides (CpG-ODNs), mimicking bacterial DNA, have recently been shown to stimulate prostate cancer invasion in
vitro via Toll-like receptor 9 (TLR9). Since cyclooxygenase 2 (COX-2), frequently overexpressed in multiple tumor types including
prostate cancer, is a causal factor for tumor development, invasion and metastasis, an interesting question is raised whether
TLR9 regulates COX-2 expression in prostate cancer cells. To address this question, herein we examined COX-2 expression in
PC-3 cells stimulated with different doses and time courses of CpG-ODNs. The regulatory role of NF-κB in TLR9-mediated COX-2
expression was also investigated. CpG-ODN was found to up-regulate the expression of COX-2 in PC-3 cells in a dose- and time-dependent
manner, but have little impact on COX-1 expression. Moreover, CpG-ODN also promoted nuclear translocation and activation of
NF-κB, which appeared to be required for COX-2 induction by CpG-ODN. Overall, TLR9 up-regulates COX-2 expression in prostate
cancer cells, at least partially through the activation of NF-κB, which may be implicated in tumor invasion and metastasis. 相似文献
999.
Zhang D Kato Y Zhang L Fujimoto M Tsutsumi N Sodmergen Sakamoto W 《The Plant cell》2010,22(11):3710-3725
FtsH is an ATP-dependent metalloprotease present as a hexameric heterocomplex in thylakoid membranes. Encoded in the Arabidopsis thaliana YELLOW VARIEGATED2 (VAR2) locus, FtsH2 is one isoform among major Type A (FtsH1/5) and Type B (FtsH2/8) isomers. Mutants lacking FtsH2 (var2) and FtsH5 (var1) are characterized by a typical leaf-variegated phenotype. The functional importance of the catalytic center (comprised by the zinc binding domain) in FtsH2 was assessed in this study by generating transgenic plants that ectopically expressed FtsH2(488), a proteolytically inactive version of FtsH2. The resulting amino acid substitution inhibited FtsH protease activity in vivo when introduced into Escherichia coli FtsH. By contrast, expression of FtsH2(488) rescued not only leaf variegation in var2 but also seedling lethality in var2 ftsh8, suggesting that the protease activity of Type B isomers is completely dispensable, which implies that the chloroplastic FtsH complex has protease sites in excess and that they act redundantly rather than coordinately. However, expression of FtsH2(488) did not fully rescue leaf variegation in var1 var2 because the overall FtsH levels were reduced under this background. Applying an inducible promoter to our complementation analysis revealed that rescue of leaf variegation indeed depends on the overall amount of FtsH. Our results elucidate protein activity and its amount as important factors for the function of FtsH heterocomplexes that are composed of multiple isoforms in the thylakoid membrane. 相似文献
1000.
Guoyong Hu Jiaqin Shen Li Cheng Di Xiang Zhonghui Zhang Miao He Huili Lu Shunying Zhu Mingyuan Wu Yan Yu Xingpeng Wang Wei Han 《Protein expression and purification》2010,69(2):186-190
Regenerating gene (Reg) IV is a newly discovered member of the regenerating gene family belonging to the calcium (C-type) dependent lectin superfamily. Reg IV is highly expressed in the gastrointestinal tract and markedly up-regulated in colon adenocarcinoma, pancreatic cancer, gastric adenocarcinoma, and inflammatory bowel disease. However, the physiological and pathological functions of Reg IV are largely unknown, partly due to the limited access of the bioactive protein. We report here the first expression and purification of Reg IV proteins using a prokaryotic system. Human Reg IV was expressed in Escherichia coli as an insoluble protein which was identified in the fraction of inclusion body after ultrasonication of the bacteria. After the protein aggregate was solubilized by guanidine–HCl, it was refolded by sucrose and arginine-assisted procedures and purified using cation-exchange chromatography. The protein identity and purity of the final preparation were confirmed by analysis of the protein mass and immune specificity in SDS–PAGE, Western blotting, and HPLC assay. The biological activity of the protein was determined by the HCT116 and HT29 cell proliferation assays. The highly purified bioactive human Reg IV should aid in further characterization of its physiological and pathological functions. 相似文献