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Relative affinity of Ca(II) and Mg(II) ions for human and bovine prothrombin and fragment 1 总被引:1,自引:0,他引:1
D W Deerfield D L Olson P Berkowitz K A Koehler L G Pedersen R G Hiskey 《Biochemical and biophysical research communications》1987,144(1):520-527
Equilibrium dialysis results are presented for Ca(II) and Mg(II) ion binding to human and bovine prothrombin and fragment 1. Ca(II) ions bind cooperatively, Mg(II) does not. 相似文献
3.
Katrin Kausch Clemens R. Müller Tiemo Grimm Kenneth Ricker Marcella Rietschel Sabine Rudnik-Schöneborn Klaus Zerres 《Human genetics》1991,86(3):317-318
Summary Two recent articles have reported the linkage of a gene for recessive spinal muscular atrophy (SMA) on the chromosome region 5q11.2–13.3. Our data show no linkage of the dominantly inherited forms of SMA to this chromosome region. 相似文献
4.
Katrin Lineruth 《Genetica》1986,78(1):33-37
The protein synthesis pattern of a set of stage and tissue specific proteins has previously been described in Drosophila melanogaster. The analysis of this set of follicle cell proteins (Fc proteins) is here extended to cover several sibling species of Drosophila melanogaster, namely D. simulans, D. mauritiana, D. erecta and D. yakuba. Even though a similar set of proteins were synthesized in these species, minor differences in size of the proteins were found between the species. Some of the species exhibited variation within species. 相似文献
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This review addresses current understanding of oxygen radical mechanisms as they relate to the brain during ischemia and reperfusion. The mechanism for radical production remains speculative in large part because of the difficulty of measuring radical species in vivo. Breakdown of lipid membranes during ischemia leads to accumulation of free fatty acids. Decreased energy stores during ischemia result in the accumulation of adenine nucleotides. During reperfusion, metabolism of free fatty acids via the cyclooxygenase pathway and metabolism of adenine nucleotides via the xanthine oxidase pathway are the most likely sources of oxygen radicals. Although leukocytes have been found to accumulate in some models of ischemia and reperfusion, their mechanistic role remains in question. Therapeutic strategies aimed at decreasing brain injury have included administration of radical scavengers at the time of reperfusion. Efficacy of traditional oxygen radical scavengers such as superoxide dismutase and catalase may be limited by their inability to cross the blood-brain barrier. Lipid-soluble antioxidants appear more efficacious because of their ability to cross the blood-brain barrier and because of their presence in membrane structures where peroxidative reactions can be halted. 相似文献
7.
Abamectin was fed to German cockroaches, Blattella germanica (L.), in non-choice tests. LT50s and LC50s were estimated by probit analysis. The LT50s for the German cockroach ranged from 4.4 to 1.7 d for males, from 9.0 to 2.4 d for females, and from 4.4 to 1.6 d for nymphs for bait concentrations of abamectin between 0.0025 and 0.0500%. The LC50s of abamectin were 0.0110 and 0.0040% from males, 0.0240 and 0.0090% for females, and 0.0200 and 0.0080% for nymphs at 3 and 6 d, respectively. The LT50 values of 0.0550% abamectin bait were 3.4, 3.4, 2.4, 7.5, 2.9, and 4.5 d for Periplaneta americana (L.), P. fuliginosa (Serville), P. brunnea Burmeister, P. australasiae (F.), Blatta orientalis L., and Supella longipalpa (Serville). Although the bait was effective against various cockroach species, time to death for the larger species was longer than for the German cockroach. In preference tests in which male German cockroaches were allowed to feed on rat chow or abamectin bait, all died within 5 d of exposure to abamectin bait. Abamectin bait consumption was not significantly lower than that of untreated rat chow. Arena tests with 0.0550% abamectin bait resulted in 31-75% mortality of German cockroaches after 9 d, with most control being achieved by treating harborages with the bait. The hydramethylnon standard resulted in 65% mortality after 9 d. 相似文献
8.
Abnormal concentrations of B vitamins and amino acids in plasma, bile, and liver of chicks with aflatoxicosis. 总被引:2,自引:2,他引:0 下载免费PDF全文
Graded levels of aflatoxin fed to broiler chickens for 3 weeks decreased the levels of most B vitamins in plasma, bile, and liver and decreased all free and hydrolyzed amino acids from peptides in plasma. The levels of thiamine, riboflavin, vitamin B6, pantothenic acid, and choline decreased by more than 60% in bile; vitamin B6, pantothenic acid, and choline decreased by more than 49% in plasma; thiamine, vitamin B6, pantothenic acid, choline, folate, and niacin decreased by more than 19% in liver; and only bile and plasma levels of folate increased (78 and 12%, respectively) with a dietary level of 5 microgram of aflatoxin per g of feed. Plasma levels of cystine and cysteine, methionine, threonine, serine, and aspartic acid decreased by more than 37%, whereas valine, lysine, leucine, histidine, hydroxyproline, and alanine decreased by more than 9% with 2.5 microgram of aflatoxin per g of feed. The data suggest that aflatoxin interferes with the metabolism of B vitamins and amino acids in chicks. However, these changes may be measuring the effects of aflatoxin-induced hepatic necrosis. 相似文献
9.
Lineage-specific evolution and gene flow in Listeria monocytogenes are independent of bacteriophages
Roxana Zamudio Richard D. Haigh Joseph D. Ralph Megan De Ste Croix Taurai Tasara Katrin Zurfluh Min Jung Kwun Andrew D. Millard Stephen D. Bentley Nicholas J. Croucher Roger Stephan Marco R. Oggioni 《Environmental microbiology》2020,22(12):5058-5072
Listeria monocytogenes is a foodborne pathogen causing systemic infection with high mortality. To allow efficient tracking of outbreaks a clear definition of the genomic signature of a cluster of related isolates is required, but lineage-specific characteristics call for a more detailed understanding of evolution. In our work, we used core genome MLST (cgMLST) to identify new outbreaks combined to core genome SNP analysis to characterize the population structure and gene flow between lineages. Whilst analysing differences between the four lineages of L. monocytogenes we have detected differences in the recombination rate, and interestingly also divergence in the SNP differences between sub-lineages. In addition, the exchange of core genome variation between the lineages exhibited a distinct pattern, with lineage III being the best donor for horizontal gene transfer. Whilst attempting to link bacteriophage-mediated transduction to observed gene transfer, we found an inverse correlation between phage presence in a lineage and the extent of recombination. Irrespective of the profound differences in recombination rates observed between sub-lineages and lineages, we found that the previously proposed cut-off of 10 allelic differences in cgMLST can be still considered valid for the definition of a foodborne outbreak cluster of L. monocytogenes. 相似文献
10.
A major gibberellic Acid-induced barley aleurone cysteine proteinase which digests hordein : purification and characterization 总被引:3,自引:4,他引:3 下载免费PDF全文
We previously described the purification and characterization of a 37,000 Mr cysteine proteinase, designated EP-A, from gibberellic acid (GA3)-induced barley (Hordeum vulgare L.) aleurone layers (S Koehler, T-HD Ho [1988] Plant Physiol 87: 95-103). A second, more abundant protease has now been purified from this tissue. This protease, designated EP-B, has an apparent Mr of 30,000 on 10% sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). It resolves into two bands during native isoelectric focusing with pl of 4.6 to 4.7. The analysis of hemoglobin digestion products by both gradient SDS-PAGE and Bio-Gel P2 chromatography, the inhibition of protease activity by E-64, leupeptin, iodoacetate, and p-hydroxymercuribenzoate, and N-terminal amino acid sequence analysis all indicate that EP-B is a cysteine proteinase. The first 22 amino acids at the N terminus of EP-B have been determined, and their sequence is 90% similar to that of EP-A. EP-B has properties similar to EP-A; however, EP-B is much more sensitive to high pH during gel electrophoresis and therefore is not detectable on native activity gels used to detect EP-A. Its pH optimum against azocasein and hemoglobin is 4.5 to 4.6. Both of these proteinases digest hordeins enriched for the B and D fractions into similar peptides of 25,000 to 2,000 Mr as determined by gradient SDS-PAGE. 相似文献