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961.
van Reeuwijk J Grewal PK Salih MA Beltrán-Valero de Bernabé D McLaughlan JM Michielse CB Herrmann R Hewitt JE Steinbrecher A Seidahmed MZ Shaheed MM Abomelha A Brunner HG van Bokhoven H Voit T 《Human genetics》2007,121(6):685-690
Intragenic homozygous deletions in the Large gene are associated with a severe neuromuscular phenotype in the myodystrophy (myd) mouse. These mutations result in a virtual lack of glycosylation of α-dystroglycan. Compound heterozygous LARGE mutations have been reported in a single human patient, manifesting with mild congenital muscular dystrophy (CMD) and severe
mental retardation. These mutations are likely to retain some residual LARGE glycosyltransferase activity as indicated by
residual α-dystroglycan glycosylation in patient cells. We hypothesized that more severe LARGE mutations are associated with a more severe CMD phenotype in humans. Here we report a 63-kb intragenic LARGE deletion in a family with Walker-Warburg syndrome (WWS), which is characterized by CMD, and severe structural brain and eye
malformations. This finding demonstrates that LARGE gene mutations can give rise to a wide clinical spectrum, similar as for other genes that have a role in the post-translational
modification of the α-dystroglycan protein.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
962.
A new species, Laccobius (Dimorpholaccobius) hopaensis sp. n. is described and Laccobius (Dimorpholaccobius) hoberlandti Gentili, 1982 is recorded from Turkey for the first time. In addition, a list of Laccobius Erichson, 1837 species known from Turkey is presented. 相似文献
963.
Optimization of solid substrate fermentation of wheat straw 总被引:9,自引:0,他引:9
Optimal conditions for solid substrate fermentation of wheat straw with Chaetomium cellulolyticum in laboratory-scale stationary layer fermenters were developed. The best pretreatment for wheat straw was ammonia freeze explosion, followed by steam treatment, alkali treatment, and simple autoclaving. The optimal fermentation conditions were 80% (w/w) moisture content; incubation temperature of 37 degrees C; 2% (w/w) unwashed mycelial inoculum; aeration at 0.12 L/h/g; substrate thickness of 1 to 2 cm; and duration of three days. Technical parameters for this optimized fermentation were: degree of substance utilization, 27.2%; protein yield/substrate, 0.09 g; biomass yield/bioconverted substrate, 0.40 g; degree of bioconversion of total available sugars in the substrate, 60.5%; specific efficiency of bioconversion, 70.8%; and overall efficiency of biomass production from substrate, 42.7%. Mixed culturing of Candida utilis further increased biomass production by 20%. The best mode of fermentation was a semicontinuous fed-batch fermentation where one-half of the fermented material was removed at three-day intervals and replaced by fresh substrate. In this mode, protein production was 20% higher than in batch mode, protein productivity was maintained over 12 days, and sporulation was prevented. 相似文献
964.
Hanan Dahche AbdulShakur Abdullah M. Ben Potters Peter J. Kennelly 《Extremophiles : life under extreme conditions》2009,13(2):371-377
The genomes of virtually all free-living archaeons encode one or more deduced protein-serine/threonine/tyrosine kinases belonging
to the so-called eukaryotic protein kinase superfamily. However, the distribution of their cognate protein-serine/threonine/phosphatases
displays a mosaic pattern. Thermoplasma volcanium is unique among the Archaea inasmuch as it is the sole archaeon whose complement of deduced phosphoprotein phosphatases includes a member of the PPM-family
of protein-serine/threonine phosphatases—a family that originated in the Eucarya. A recombinant version of this protein, TvnPPM, exhibited protein-tyrosine phosphatase in addition to its predicted protein-serine/threonine
phosphatase activity in vitro. TvnPPM is the fourth member of the PPM-family shown to exhibit such dual-specific capability, suggesting that the ancestral
versions of this enzyme exhibited broad substrate specificity. Unlike most other archeaons, the genome of T. volcanium lacks open reading frames encoding stereotypical protein-tyrosine phosphatases. Hence, the dual-specificity of TvnPPM may
account for its seemingly aberrant presence in an archaeon. 相似文献
965.
Dendrobium Sonia 17 calluses were used for co-transformation study using particle bombardment. The bombarded transformed callus tissues were selected using half-strength MS medium containing 25 mg dm−3 hygromycin. Expression of green fluorescent protein (GFP) was observed in the callus and protocorm-like body (PLBs) tissues survived on the selection medium. The presence of green fluorescence protein (sgfp), hygromycin-B-phosphotransferase (hptII) and β-glucuronidase (uidA) genes in the transformed tissues were verified using PCR, Southern blot and dot blot analyses. Based on the results from PCR and expression of sgfp and uidA genes in the calluses and PLBs survived from hygromycin selection, we reported the co-transformation of sgfp, hptII and uidA genes into Dendrobium Sonia 17. GFP-expressing tissues were also observed in the regenerated transformed plantlets. 相似文献
966.
Ling C Ishiai M Ali AM Medhurst AL Neveling K Kalb R Yan Z Xue Y Oostra AB Auerbach AD Hoatlin ME Schindler D Joenje H de Winter JP Takata M Meetei AR Wang W 《The EMBO journal》2007,26(8):2104-2114
The Fanconi anemia (FA) core complex plays a central role in the DNA damage response network involving breast cancer susceptibility gene products, BRCA1 and BRCA2. The complex consists of eight FA proteins, including a ubiquitin ligase (FANCL) and a DNA translocase (FANCM), and is essential for monoubiquitination of FANCD2 in response to DNA damage. Here, we report a novel component of this complex, termed FAAP100, which is essential for the stability of the core complex and directly interacts with FANCB and FANCL to form a stable subcomplex. Formation of this subcomplex protects each component from proteolytic degradation and also allows their coregulation by FANCA and FANCM during nuclear localization. Using siRNA depletion and gene knockout techniques, we show that FAAP100-deficient cells display hallmark features of FA cells, including defective FANCD2 monoubiquitination, hypersensitivity to DNA crosslinking agents, and genomic instability. Our study identifies FAAP100 as a new critical component of the FA-BRCA DNA damage response network. 相似文献
967.
Aijaz Rasool Chaudhry R. Ahmed Ahmad Irfan Mazmira Mohamad Shabbir Muhammad Bakhtiar Ul Haq Abdullah G. Al-Sehemi Y. Al-Douri 《Journal of molecular modeling》2016,22(10):248
Some important optoelectronic properties of naphtho[2,1-b:6,5-b′]difuran (DPNDF) and its two derivatives have been limelighted by applying the density functional theory (DFT). Due to their low cost, high stability and earth abundance, the DPNDF and its derivatives are considered as potential organic semiconductor materials for their optoelectronics applications. Highly proficient derivatives are obtained systematically by attaching –CN (cyanide) to DPNDF at various sites. Our calculations indicate that DPNDF has a wide and direct band gap with an energy gap of 3.157 eV. Whereas the band gaps of its derivatives are found to be decreased by 88 meV for derivative “a” and 300 meV for derivative “b” as a consequence of p orbitals present in C and N atoms in derivative structures. The narrowing of the energy gap and density of states for the derivatives of DPNDF in the present investigation suggest that energy gap can be engineered for desirable optoelectronic applications via derivatives designing. Furthermore, their obtained results for optical parameters such as the dielectric and conductivity functions, reflectivity, refractive index, and the extinction coefficients endorses their aptness for optoelectronic applications. 相似文献
968.
Sulaiman Ali Alharbi Bassam H. Mashat Naif Abdullah Al-Harbi Milton Wainwright Abeer S. Aloufi Sulamain Alnaimat 《Saudi Journal of Biological Sciences》2012,19(2):147-150
Bismuth salicylate was found to inhibit the growth of a range of bacteria and yeast, “Candida albicans”. In general the growth of bacteria did not result in increase in bismuth solubilisation, in contrast, bismuth solubilisation increased following the growth of C. albicans. A significant increase in the biomass (dry weight) of Aspergillus niger and Aspergillus oryzae occurred in vitro when these fungi were grown in the presence of bismuth salicylate. Biomass increase occurred over a range of bismuth compound additions, which in the case of A. oryzae was associated with increase in the solubilisation of the insoluble bismuth compounds. 相似文献
969.
Zinc tetraphenylporphyrin (ZnTPP) was modified by a push-pull strategy and then density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were performed for the resulting derivatives. The smallest HOMO-LUMO energy gaps were found in ZnTPP-6 and ZnTPP-7, which had nitro substituents and a conjugated chain, while the largest was observed for ZnTPP-5. The energy gaps of all of the systems designed in this work were smaller than that of ZnTPP. Clear intramolecular charge transfer was observed from donor to acceptor in ZnTPP-6 and ZnTPP-7, which had nitro groups at positions R8, R9, and R10, as well as in ZnTPP-3 and ZnTPP-4, which had cyano groups at those positions. The narrow band gaps (compared to that of ZnTPP) of these designed systems, where the LUMO is above the conduction band of TiO(2) and the HOMO is below the redox couple, indicate that they are efficient sensitizers. The B bands of these newly designed derivatives, except for ZnTPP-5, are redshifted compared with the B band of ZnTPP. 相似文献
970.
L.Z. JIN Y.W. Ho N. Abdullah M.A. Ali S. Jalaludin 《Letters in applied microbiology》1996,23(2):67-71
L.Z. JIN, Y.W. HO, N. ABDULLAH, M.A. ALI AND S. JALALUDIN. 1996. Twelve Lactobacillus strains isolated from chicken intestine, which demonstrated a strong and moderate capacity to adhere to the ileal epithelial cells in vitro , were used to investigate their inhibitory ability against five strains of salmonella, i.e. Salmonella enteritidis 935/79, Salm. pullorum, Salm. typhimurium, Salm. blockley and Salm. enteritidis 94/448, and three serotypes of Escherichia coli , viz. E. coli O1 : K1, O2 : K1 and O78 : K80. The results showed that all the 12 Lactobacillus isolates were able to inhibit the growth of the five strains of salmonella, and the three strains of E. coli in varying degrees. Generally, they were more effective in inhibiting the growth of salmonella than E. coli . Inhibition of the pathogenic bacteria was probably due to the production of organic acids by the Lactobacillus isolates. 相似文献