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J J St?pán K H Lau S Mohan M Kraenzlin D J Baylink 《Biochemical and biophysical research communications》1989,165(3):1027-1034
Tartrate-resistant acid phosphatases types 5a and 5b were purified from human hairy cell leukemia spleen by sequential chromatography on Phenyl-Sepharose, CM-Sepharose, concanavalin A-Sepharose, FPLC Superose-12 and FPLC Mono-S. The purification over the original tissue extract was 1150- and 3300-fold, with a yield of 2.1% and 2.5%, respectively. Gel filtration indicated an Mr of about 30000 for both forms. There was a N-terminal sequence identity between the two enzymes. However, they appeared to be different as assessed by cation exchange chromatography and amino acid composition. 相似文献
135.
There was a strong correlation between measurements of red core disease of strawberry, assessed as percentage lengths of the adventitious roots with red steles, and ELISA values obtained from the same root systems using a polyclonal antiserum raised to Phytophthora fragariae. ELISA grouped twelve host cultivar/pathogen isolate combinations into three categories, highly resistant, partially resistant and susceptible, which agreed with disease incidence after inoculation. 相似文献
136.
Various process alternatives and designs of using a filter containing cellular adsorbents to remove trace viral contaminants from blood and other protein solutions have been studied. Sterilization charts have been developed that can be used to estimate the filter size required to achieve a desired sterilization criterion. A parametric study was carried out to identify various process parameters that may affect this physical trace removal process. It has been demonstrated that the adsorption rate constant is a critical parameter in the design of an efficient cellular filter for viral contaminant removal. This constant is characteristic of the virus-cell system under consideration and is shown to be particularly sensitive to the cell surface receptor density, adsorbent diameter, and fluid flow rate. Higher log titer reduction in virus concentrations can be achieved with low flow rates and no recycle. Preliminary analyses indicate the feasibility of using a magnetically stabilized fluidized filter (MSFF) reactor design for effective virus removal from these complex solutions. 相似文献
137.
Nucleotide sequence, organisation and structural analysis of the products of genes in the nirB-cysG region of the Escherichia coli K-12 chromosome 总被引:12,自引:0,他引:12
T Peakman J Crouzet J F Mayaux S Busby S Mohan N Harborne J Wootton R Nicolson J Cole 《European journal of biochemistry》1990,191(2):315-323
The DNA sequence and derived amino-acid sequence of a 5618-base region in the 74-min area of the Escherichia coli chromosome has been determined in order to locate the structural gene, nirB, for the NADH-dependent nitrite reductase and a gene, cysG, required for the synthesis of the sirohaem prosthetic group. Three additional open reading frames, nirD, nirE and nirC, were found between nirB and cysG. Potential binding sites on the NirB protein for NADH and FAD, as well as conserved central core and interface domains, were deduced by comparing the derived amino-acid sequence with those of database proteins. A directly repeated sequence, which includes the motif -Cys-Xaa-Xaa-Cys-, is suggested as the binding site for either one [4Fe-4S] or two [2Fe-2S] clusters. The nirD gene potentially encodes a soluble, cytoplasmic protein of unknown function. No significant similarities were found between the derived amino-acid sequence of NirD and either NirB or any other protein in the database. If the nirE open reading frame is translated, it would encode a 33-amino-acid peptide of unknown function which includes 8 phenylalanyl residues. The product of the nirC gene is a highly hydrophobic protein with regions of amino-acid sequence similar to cytochrome oxidase polypeptide 1. 相似文献
138.
Mark A. Seefeld Hong Lin Joerg Holenz Dave Downie Brian Donovan Tingting Fu Kishore Pasikanti Wei Zhen Matthew Cato Khuram W. Chaudhary Pat Brady Tania Bakshi Dwight Morrow Sridharan Rajagopal Swapan Kumar Samanta Naveena Madhyastha Bharathi Mohan Kuppusamy Robert W. Dougherty Yasuji Matsuoka 《Bioorganic & medicinal chemistry letters》2018,28(23-24):3793-3797
Neuronal voltage-gated potassium channels, KV7s, are the molecular mediators of the M current and regulate membrane excitability in the central and peripheral neuronal systems. Herein, we report novel small molecule KV7 openers that demonstrate anti-seizure activities in electroshock and pentylenetetrazol-induced seizure models without influencing Rotarod readouts in mice. The anti-seizure activity was determined to be proportional to the unbound concentration in the brain. KV7 channels are also expressed in the bladder smooth muscle (detrusor) and activation of these channels may cause localized undesired effects. Therefore, the impact of individual KV7 isoforms was investigated in human detrusor tissue using a panel of KV7 openers with distinct activity profiles among KV7 isoforms. KCNQ4 and KCNQ5 mRNA were highly expressed in detrusor tissue, yet a compound that has significantly reduced activity on homomeric KV7.4 did not reduce detrusor contraction. This may suggest that the homomeric KV7.4 channel plays a less significant role in bladder contraction and further investigation is needed. 相似文献
139.
Mayank Mittal Sanjay Kumar Biswas Vandana Singh Nidhi Arela Vishwa Mohan Katoch Ram Das Virendra Singh Yadav Bharat Bajaj Keshar Kunja Mohanty 《Molecular biology reports》2018,45(4):469-476
Tuberculosis (TB) is a disease of global importance. There is an increasing recognition of the role of Toll like receptors, important pattern recognition receptors of host immune system, in determining the susceptibility or resistance to TB in various populations. In an attempt to examine the importance of Toll like receptors in immune response to Mycobacterium tuberculosis infection, we explored two variants each of TLR2 and TLR9 in a population residing in Uttar Pradesh, India. Genotyping was performed to detect -196 to -174 del polymorphism and G2258A SNP (Arg753Gln, rs5743708) in TLR2 gene and -T1237C (rs5743836) and G2848A (rs352140) SNP in TLR9 gene in patients with pulmonary TB and healthy controls. The A allele of G2848A SNP in TLR9 gene was found with a marginally higher frequency among TB patients as compared to healthy controls, suggesting that A allele at position 2848 of TLR9 gene may be associated with susceptibility to TB in North Indian population [p?=?0.05, Mantel–Haenszel OR?=?1.34, 95% CI (1.0–1.82)]. 相似文献
140.