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排序方式: 共有977条查询结果,搜索用时 21 毫秒
1.
Activity of phosphate-dissolving bacteria in Egyptian soils 总被引:1,自引:0,他引:1
S. M. Taha S. A. Z. Mahmoud A. Halim El-Damaty A. M. Abd El-Hafez 《Plant and Soil》1969,31(1):149-160
2.
A. M. Abo-Shady S. M. Abou-El-Souod Abd El-Raheem R. El-Shanshoury Y. A. G. Mahmoud 《World journal of microbiology & biotechnology》1992,8(4):385-386
Protoplasts were obtained from the filamentous blue-green algaSpirulina platensis by treating the filaments with 0.05% (w/v) lysozyme in 0.03m phosphate buffer. The protoplasts regenerated cell walls and formed colonies when plated on a regeneration medium. The highest percentage of regeneration, 40% was obtained after 21 days. 相似文献
3.
Barbus bynni begins to mature at Age IV. Ripening of gonads of mature fish starts in May when water temperature approaches the annual maximum. However, the spawning season coincides with the onset of the flood season in July. These facts, as well as the cyclic growth of the gonads, show that B. bynni spawns once a year. Fecundity varies with size of fish and gonads. However, this levels off in the middle size group. At this age the fecundity was estimated to be 1 424 693 eggs. 相似文献
4.
Basic knowledge on the feeding ecology of one of the common and commercially important fish species in Jebel Aulia Reservoir is provided.The structure of the feeding apparatus indicates that Labeo niloticus is a bottom feeder, depending on soft and decayed vegetation, organic debris and whatever small organisms found within. However, juveniles and fry are prone to explore all layers and depths of the river selectively for plankton. There is little evidence of seasonal selection of food. Changes in diet quality are governed by the availability of type of food. Variability of feeding activity is connected with climate and breeding season. 相似文献
5.
Fungal spore populations in the outdoor and indoor atmosphere of Ismailia have been studied during the period from March 1992
to May 1993. A total of 23 350 cfu and 73 species were recorded,Cladosporium cladosporioides, Aureobasidium pullulans andAspergillus flavus were the most abundant. The indoor and outdoor mycoflora showed marked quantitative and qualitative differences. In view
of count, recorded species could be categorized into three groups as follows: (a) species showing higher counts in out- than
indoor, (b) species showing the opposite trend i.e. lower counts in out-door than indoor, (c) species showing approximately
equal counts in out- and indoor. Regarding seasonal periodicity, March and either September or October showed the highest
count for both normal fungal flora (NFF) and opportunistic fungal flora (OFF). While January and July showed the lowest count
of them both, May but not July was the lowest as for outdoor NFF. 相似文献
6.
Polysaccharide production by Aureobasidium pullulans: factors affecting polysaccharide formation 总被引:1,自引:0,他引:1
S. M. Badr-Eldin O. M. El-Tayeb H. G. El-Masry F. H. A. Mohamad O. A. Abd El-Rahman 《World journal of microbiology & biotechnology》1994,10(4):423-426
Aureobasidium pullulans NRRL 6220 synthesized polysaccharide most actively in media containing sucrose, fructose or maltose with (NH4)2SO4 (0.6 g/l) or ammonium acetate giving greatest yields of the polysaccharide. With (NH4)2SO4 at 1.2 g/l, production of polysaccharide was decreased considerably. Polysaccharide production was highest with an initial pH of 6.5 while biomass formation was better below an initial pH of 5.5. Optimum phosphate concentration for polysaccharide production was 0.03 m.S.M. Badr-Eldin, H.G. El-Masry and O.A. Abd El-Rahman are with the Microbial Chemistry Department, National Research Center, Dokki, Cairo, Egypt; F.H.A. Mohamad is with the Chemical Engineering and Pilot Plant Department, National Research Center, Dokki, Cairo, Egypt. O.M. El-Tayeb is with the Microbiology Department, Faculty of Pharmacy, Cairo University, Egypt. 相似文献
7.
Alice Abd El-Aleem Ingolf Böhm Samia Temtamy Mostafa El-Awady Mohamed Awadalla Jörg Schmidtke Manfred Stuhrmann 《Human genetics》1995,96(5):577-584
Molecular genetic analysis of individuals from 6 Egyptian and 33 German families with fragile X syndrome and 240 further patients with mental retardation was performed applying a completely non-radioactive system. The aim of our study was the development of a non-radioactive detection method and its implementation in molecular diagnosis of the fragile X syndrome. Furthermore, we wanted to assess differences in the mutation sizes between Egyptian and German patients and between Egyptian and German carriers of a premutation. Using non-radioactive polymerase chain reaction (PCR), agarose gel electrophoresis and blotting of the PCR products, followed by hybridisation with a digoxigenin-labelled oligonucleotide probe (CGG)5 and chemiluminescent detection, we identified the fragile X full mutation (amplification of a CGG repeat in the FMR-1 gene ranging from several hundred to several thousand repeat units) in all patients. We observed no differences in the length of the CGG repeat between the Egyptian and German patients and carriers, respectively. However, in one prenatal diagnosis, we detected only one normal sized allele in a female fetus using the PCR-agarose assay, whereas Southern blot analysis with the digoxigenin labelled probe StB 12.3 revealed presence of a full mutation. Our newly established nonradioactive genomic blotting method is based on the conventional radioactive Southern blot analysis. Labelling of the probe StB 12.3 with digoxigenin via PCR allowed the detection of normal, premutated and fully mutated alleles. For exact sizing of small premutated or large normal alleles, we separated digoxigenin labelled PCR products through denaturing poly-acrylamide gelelectrophoresis (PAGE) and transfered them to a nylon membrane using a gel dryer. The blotted PCR-fragments can easily be detected with alkaline phosphate-labelled anti-digoxigenin antibody. The number of trinucleotide repeat units can be determined by scoring the detected bands against a digoxigenated M13 sequencing ladder. Our newly developed digoxigenin/chemiluminescence approach using PCR and Southern blot analysis provides reliable results for routine detection of full fragile X mutations and premutations. 相似文献
8.
Amira I. Sayed Yara E. Mansour Mohamed A. Ali Omnia Aly Zainab M. Khoder Ahmed M. Said Samar S. Fatahala Rania H. Abd El-Hameed 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):1821
Current medical approaches to control the Covid-19 pandemic are either to directly target the SARS-CoV-2 via innovate a defined drug and a safe vaccine or indirectly target the medical complications of the virus. One of the indirect strategies for fighting this virus has been mainly dependent on using anti‐inflammatory drugs to control cytokines storm responsible for severe health complications. We revealed the discovery of novel fused pyrrolopyrimidine derivatives as promising antioxidant and anti-inflammatory agents. The newly synthesised compounds were evaluated for their in vitro anti-inflammatory activity using RAW264.7 cells after stimulation with lipopolysaccharides (LPS). The results revealed that 3a, 4b, and 8e were the most potent analogues. Molecular docking and simulations of these compounds against COX-2, TLR-2 and TLR-4 respectively was performed. The former results were in line with the biological data and proved that 3a, 4b and 8e have potential antioxidant and anti-inflammatory effects. 相似文献
9.
Impacts of cell surface characteristics on population dynamics in a sequencing batch yeast reactor treating vegetable oil-containing wastewater 总被引:1,自引:0,他引:1
Ten yeast strains acquired from different sources and capable of utilizing vegetable oil or related compounds (fatty acid
or oleic acid) as sole carbon sources were inoculated into a sequencing batch reactor (SBR) for the treatment of high-strength
vegetable oil-containing wastewater. The SBR system stably removed >89% of chemical oxygen demand (COD) and >99% of oil when
fed with wastewater containing 15 g/L COD and 10 g/L oil in average. Denaturing gradient gel electrophoresis of polymerase
chain reaction-amplified 26S rRNA genes showed that among the ten yeast strains, only Candida lipolytica, Candida tropicalis, and Candida halophila were dominant in the system. To elucidate the major factors affecting the selection of yeast strains in the SBR system, the
three dominant strains were compared with two non-dominant strains in terms of COD removal performance, biomass yield, cell
settleability, cell flocculation ability, cell emulsification ability, and surface hydrophobicity. Results showed that hydrophobicity
and emulsification ability of yeast cells were the two most important factors determining the selection of yeast strains in
the treatment of high-strength oil-containing wastewater. 相似文献
10.
AFN-1252 is a potent inhibitor of enoyl-ACP reductase from Burkholderia pseudomallei—Crystal structure,mode of action,and biological activity
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Krishnamurthy Narasimha Rao Anirudha Lakshminarasimhan Sarah Joseph Swathi U Lekshmi Ming-Seong Lau Mohammed Takhi Kandepu Sreenivas Sheila Nathan Rohana Yusof Noorsaadah Abd Rahman Murali Ramachandra Thomas Antony Hosahalli Subramanya 《Protein science : a publication of the Protein Society》2015,24(5):832-840
Melioidosis is a tropical bacterial infection caused by Burkholderia pseudomallei (B. pseudomallei; Bpm), a Gram-negative bacterium. Current therapeutic options are largely limited to trimethoprim-sulfamethoxazole and β-lactam drugs, and the treatment duration is about 4 months. Moreover, resistance has been reported to these drugs. Hence, there is a pressing need to develop new antibiotics for Melioidosis. Inhibition of enoyl-ACP reducatase (FabI), a key enzyme in the fatty acid biosynthesis pathway has shown significant promise for antibacterial drug development. FabI has been identified as the major enoyl-ACP reductase present in B. pseudomallei. In this study, we evaluated AFN-1252, a Staphylococcus aureus FabI inhibitor currently in clinical development, for its potential to bind to BpmFabI enzyme and inhibit B. pseudomallei bacterial growth. AFN-1252 stabilized BpmFabI and inhibited the enzyme activity with an IC50 of 9.6 nM. It showed good antibacterial activity against B. pseudomallei R15 strain, isolated from a melioidosis patient (MIC of 2.35 mg/L). X-ray structure of BpmFabI with AFN-1252 was determined at a resolution of 2.3 Å. Complex of BpmFabI with AFN-1252 formed a symmetrical tetrameric structure with one molecule of AFN-1252 bound to each monomeric subunit. The kinetic and thermal melting studies supported the finding that AFN-1252 can bind to BpmFabI independent of cofactor. The structural and mechanistic insights from these studies might help the rational design and development of new FabI inhibitors. 相似文献