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11.
Khalid M. Chraibi B. Alain Latche Jean-Paul Roustan Jean Fallot 《Plant cell reports》1991,10(4):204-207
The effects of CoCl2, AgNO3 and ethylene released by exogenous 2-chloroethylphosphonic acid (Ethephon), were studied on shoot regeneration from cotyledons of Helianthus annuus cv. E8206R, a poorly regenerative cultivar. Inhibition of ethylene biosynthesis by CoCl2, at concentrations of 20 K, provoked a substantial enhancement of shoot regeneration (30 %): the control was poorly regenerative. However, CoCl2 had no effect when Ethephon was supplied. Inhibition of ethylene action by AgNO3, at concentrations of 10–25 M, caused a significant increase in plant regeneration: 25 % instead of 1.2 % in the control. Furthermore, addition of Ethephon to AgNO3-treated tissues failed to reduce the stimulation of shoot regeneration caused by AgNO3. On the basis of these findings, it is suggested that ethylene inhibits the regeneration process from cotyledons of sunflower.Abbreviations NAA
1-naphthalene acetic acid
- BAP
6-benzylamino-purine
- GA3
gibberellic acid
- Ethephon
2-chloroethylphosphonic acid
- MS
Murashige and Skoog medium
- AVG
aminoethoxyvinylglycine 相似文献
12.
Purification and Partial Characterization of a Prolyl-Dipeptidyl Aminopeptidase from Lactobacillus helveticus CNRZ 32 总被引:8,自引:6,他引:2
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X-prolyl-dipeptidyl aminopeptidase, which hydrolyzed Gly-Pro-p-nitroanilide (relative activity [RA] = 100%) and Arg-Pro-p-nitroanilide (RA, 130%), was purified to homogeneity from the cell extract of Lactobacillus helveticus CNRZ 32. The enzyme also hydrolyzed Ala-Pro-Gly (RA, 11%) and Ala-Ala-p-nitroanilide (RA, 2%) but was not active on Ala-Leu-Ala, dipeptides, and endopeptidase and carboxypeptidase substrates. The enzyme was purified 145-fold by streptomycin sulfate precipitation, ammonium sulfate fractionation, and a series of column chromatographies on DEAE-cellulose, arginine-Sepharose 4B, and glycyl-prolyl-AH-Sepharose 4B. The purified enzyme appeared as a single band on native polyacrylamide gel and sodium dodecyl sulfate-polyacrylamide gel electrophoreses and had a molecular weight of 72,000. Optima for activity by the purified enzyme were pH 7.0 and 40°C. The enzyme was incubated at 40°C for 15 min with various metal ions. It was activated by Mg2+ (2.5 mM), Ca2+ (0.1 to 2.5 mM), Na+ (10 to 50 mM), and K+ (10 to 50 mM) and was inhibited by Hg2+ (0.1 to 2.5 mM), Cu2+ (0.1 to 2.5 mM), and Zn2+ (0.1 to 2.5 mM). Enzyme activity was partially inhibited by EDTA (1.0 mM, 20 h at 40°C), 1,10-phenanthroline (1.0 mM, 15 min at 40°C), phenylmethylsulfonyl fluoride (1.0 mM), N-ethylmaleimide (1.0 mM), and iodoacetate (1.0 mM). It was completely inhibited by diisopropyl fluorophosphate (1.0 mM, 2 h at 40°C) and p-chloromercuribenzoate (1.0 mM, 15 min at 40°C). The enzyme was not affected by dithioerythritol (1.0 to 10 mM). 相似文献
13.
Mazhar N. Malik Laurie A. Meyers Khalid Iqbal Ashfaq M. Sheikh Lois Scotto Henryk M. Wisniewski 《Life sciences》1981,29(8):795-802
A Ca2+ activated protease(s) capable of hydrolyzing several polypeptides at neutral pH including cytoskeletal proteins, actin, myosin, tubulin and neurofilament triplet was identified in calf brain cortex. The enzyme activity precipitates at 75 mM KCl, pH 6.5 – 7.0 and is inhibited by the sulfhydryl inhibitors, N-ethylmaleimide and para-chloromercuribenzoate and the protease inhibitors, antipain, pepstatin and leupeptin, leupeptin being the most effective. 相似文献
14.
Sensitivity of glutamine synthetase assay by the hydroxamate method can be doubled by replacing ferric chloride with ferric nitrate or ferric perchlorate, each with the appropriate acid. 相似文献
15.
16.
Khalid Hussain Wali Sait Mutaib Mashraqi Asim Abdulaziz Khogeer Othman Alzahrani Nisreen M Anfinan Hesham Khalid Sait Abdulrahman Almutairi Qamre Alam 《Bioinformation》2020,16(11):882
The human epidermal growth factor (HER2) is a transmembrane receptor that is highly expressed in breast cancer and in different other cancers. Therefore, it is of interest to identify the new HER2 inhibitors from a selected 300 compounds in the ZINC database. The top two hit compounds (ZINC000014780728 (-11.0 kcal/mol) and ZINC000014762512 (-10.8 kcal/mol)) showed a high affinity with HER2 relative to the reference compound (lapatinib (-10.2 kcal/mol)) for further consideration. 相似文献
17.
Md. Ashraful Alam Milan Skalicky Muhammad Rezaul Kabir Md. Monwar Hossain Md. Abdul Hakim Md. Siddikun Nabi Mandal Rabiul Islam Md. Babul Anwar Akbar Hossain Fahmy Hassan Amaal Mohammadein Muhammad Aamir Iqbal Marian Brestic Mohammad Anwar Hossain Khalid Rehman Hakeem Ayman EL Sabagh 《Phyton》2021,90(4):1301-1320
Globally among biotic stresses, diseases like blight, rust and blast constitute prime constraints for reducing wheat
productivity especially in Bangladesh. For sustainable productivity, the development of disease-resistant lines and
high yielding varieties is vital and necessary. This study was conducted using 122 advanced breeding lines of
wheat including 21 varieties developed by Bangladesh Wheat and Maize Research Institute (BAMRI) with aims
to identify genotypes having high yield potential and resistance to leaf blight, leaf rust and blast diseases. These
genotypes were evaluated for resistance against leaf blight and leaf rust at Dinajpur and wheat blast at Jashore
under field condition. Out of 122 genotypes tested, 20 lines were selected as resistant to leaf blight based on
the area under the diseases progress curve (AUDPC) under both irrigated timely sown (ITS) and irrigated late
sown (ILS) conditions. Forty-two genotypes were found completely free from leaf rust infection, 59 genotypes
were identified as resistant, and 13 genotypes were identified as moderately resistant to leaf rust. Eighteen genotypes were immune against wheat blast, 42 genotypes were categorized as resistant, and 26 genotypes were identified as moderately resistant to wheat blast. Molecular data revealed that the 16 genotypes showed a positive 2NS
segment among the 18 immune genotypes selected against wheat blast under field conditions. The genotypes
BAW 1322, BAW 1295, and BAW 1203 can be used as earlier maturing genotypes and the genotypes BAW
1372, BAW 1373, BAW 1297 and BAW 1364 can be used for lodging tolerant due to short plant height. The genotypes WMRI Gom 1, BAW 1349 and BAW 1350 can be selected for bold grain and the genotypes WMRI Gom 1,
BAW 1297, BAW 1377 can be used as high yielder for optimum seeding condition but genotypes BAW 1377
and BAW 1366 can be used for late sown condition. The selected resistant genotypes against specific diseases can be used in the further breeding program to develop wheat varieties having higher disease resistance and
yield potential. 相似文献
18.
Khan Muhammad Tahir Zeb Muhammad Tariq Ahsan Hina Ahmed Abrar Ali Arif Akhtar Khalid Malik Shaukat Iqbal Cui Zhilei Ali Sajid Khan Anwar Sheed Ahmad Manzoor Wei Dong-Qing Irfan Muhammad 《Archives of microbiology》2021,203(1):59-66
Archives of Microbiology - Severe acute respiratory syndrome virus 2 (SARS-CoV-2) belongs to the single-stranded positive-sense RNA family. The virus contains a large genome that encodes four... 相似文献
19.
Iqra Farooq Z.A. Qadri Z.A. Rather Imtiyaz T. Nazki Neelofar Banday Sadaf Rafiq Khalid Z. Masoodi Ahmed Noureldeen Sheikh Mansoor 《Saudi Journal of Biological Sciences》2021,28(7):3701-3709
An efficient protocol for in-vitro propagation of an important ornamental crop, Petunia hybrida Vilm. Cv. “Bravo” was developed. The explants that were used to carry out the experiment were Leaf segments, nodal segments and shoot tips. Nodal segments recorded highest per cent asepsis followed by shoot tips and leaf segments. Asepsis was found to be highest when the explants were sterilized with Fungicide (Carbendazim) 0.02% for the duration of 30 min followed by 0.1% HgCl2 for duration of 10 min and then ethanol 70% for 10 s. Longer duration of the sterilant treatment showed more necrotic effects on the explants, thus mercuric chloride treatment when given for 5 min proved to be more effective in terms of survival of the explants. Maximum establishment per cent was recorded in Murashige and Skoog (MS) media fortified with BAP (1.5 mg L−1) and IBA (0.5 mg L−1) in shoot tips and nodal segments, i.e. 97.90 and 95.74% respectively. Callus was efficiently induced and developed when PGR amalgamation of BAP (0.1 mg L−1) and 2,4-D (1.5mg L−1) was used. Kinetin at the concentration of 2.0 mg L−1 along with IBA at 0.5mg L−1 recorded highest callus regeneration in both leaf and internodal segment derived callus. Maximum proliferation percent of shoots (97.90%), highest number of shoots (20.50 explant−1) and maximum length of shoot (2.70 cm) was recorded in PGR combination of IBA and BAP both at 0.5 mg L−1 concentration level. Rhizogenesis was recorded to be highest in the MS media containing IBA 1.00 mg L−1. Best hardening media which recorded maximum survival per cent 92.50% was noticed on the media formulation comprised of equal ratio of perlite and vermiculite mix, under poly house conditions. 相似文献
20.
Jamal M. Khaled Sami A. Alyahya C. Chenthis Kanisha Naiyf S. Alharbi Shine Kadaikunnan G. Ramachandran Khalid F. Alanzi G. Rajivgandhi RTV Vimala N. Manoharan 《Saudi Journal of Biological Sciences》2021,28(1):302-309
Urinary tract infections are second most important diseases worldwide due to the increased amount of antibiotic resistant microbes. Among the Gram negative bacteria, P. mirabilis is the dominant biofilm producer in urinary tract infections next to E. coli. Biofilm is a process that produced self-matrix of more virulence pathogens on colloidal surfaces. Based on the above fact, this study was concentrated to inhibit the P. mirabilis biofilm formation by various in-vitro experiments. In the current study, the anti-biofilm effect of essential oils was recovered from the medicinal plant of Solanum nigrum, and confirmed the available essential oils by liquid chromatography-mass spectroscopy analysis. The excellent anti-microbial activity and minimum biofilm inhibition concentration of the essential oils against P. mirabilis was indicated at 200 µg/mL. The absence of viability and altered exopolysaccharide structure of treated cells were showed by biofilm metabolic assay and phenol–sulphuric acid method. The fluorescence differentiation of P. mirabilis treated cells was showed with more damages by confocal laser scanning electron microscope. Further, more morphological changes of essential oils treated cells were differentiated from normal cells by scanning electron microscope. Altogether, the results were reported that the S. nigrum essential oils have anti-biofilm ability. 相似文献