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101.
102.
Annexin A2 Is a Molecular Target for TM601, a Peptide with Tumor-targeting and Anti-angiogenic Effects 总被引:1,自引:0,他引:1
Kamala Kesavan Judson Ratliff Eric W. Johnson William Dahlberg John M. Asara Preeti Misra John V. Frangioni Douglas B. Jacoby 《The Journal of biological chemistry》2010,285(7):4366-4374
TM601 is a synthetic form of chlorotoxin, a 36-amino acid peptide derived from the venom of the Israeli scorpion, Leirius quinquestriatus, initially found to specifically bind and inhibit the migration of glioma cells in culture. Subsequent studies demonstrated specific in vitro binding to additional tumor cell lines. Recently, we demonstrated that proliferating human vascular endothelial cells are the only normal cell line tested that exhibits specific binding to TM601. Here, we identify annexin A2 as a novel binding partner for TM601 in multiple human tumor cell lines and human umbilical vein endothelial cell (HUVEC). We demonstrate that the surface binding of TM601 to the pancreatic tumor cell line Panc-1 is dependent on the expression of annexin A2. Identification of annexin A2 as a binding partner for TM601 is also consistent with the anti-angiogenic effects of TM601. Annexin A2 functions in angiogenesis by binding to tissue plasminogen activator and regulating plasminogen activation on vascular endothelial cells. We demonstrate that in HUVECs, TM601 inhibits both vascular endothelial growth factor- and basic fibroblast growth factor-induced tissue plasminogen activator activation, which is required for activation of plasminogen to plasmin. Consistent with inhibition of cell surface protease activity, TM601 also inhibits platelet-derived growth factor-C induced trans-well migration of both HUVEC and U373-MG glioma cells. 相似文献
103.
R. Narayanan P. Venkateswararao V.Damodaram Chowdary 《Journal of invertebrate pathology》1982,39(3):277-280
The levels of adenine compounds in the gastropod Lymnaea luteola have been determined through ion-exchange chromatography. In snails infected with the larvae of Prosthogonimus sp., the concentration decreased. As a result, the different bioenergetic parameters like ATP/ADP, ATP/AMP, and “energy charge” were altered. 相似文献
104.
Microsomal 11α-hydroxylation of progesterone in : Part I: Characterization of the hydroxylase system
C.R. Jayanthi Prema Madyastha K.Madhava Madyastha 《Biochemical and biophysical research communications》1982,106(4):1262-1268
Microsomes (105,000xg sediment) prepared from induced cells of was found to hydroxylate progesterone to 11α-hydroxyprogesterone (11α-OHP) in high yields (85–90% in 30 min.) in the presence of NADPH and O2. The pH optimum for the hydroxylase was found to be 7.7. However, for the isolation of active microsomes grinding of the mycelium should be carried out at pH 8.3. Metyrapone, carbon monoxide, SKF-525A, p-CMB and N-methyl maleimide inhibited the hydroxylase activity indicating the involvement of cytochrome P-450 system. The inhibition of the hydroxylase by cytochrome and the presence of high levels of NADPH-cytochrome reductase in induced microsomes suggest that the reductase could be one of the components in the hydroxylase system. 相似文献
105.
Rat liver ribonuclease P was isolated from a cytosolic fraction and shown to have optimal activity in the presence of 1 mM MgCl2 and 150-200 mM KCl using Escherchia coli pre-tRNA(Tyr) as substrate. In cesium sulfate isopycnic density gradients, the enzyme had a buoyant density of 1.36 g/ml, indicating that it is a ribonucleoprotein complex. Analysis of the RNAs in the enzyme sample purified through two successive Cs2SO4 density gradient steps revealed the copurification of two major species of RNA (RRP1 and RRP2) along with several less abundant RNAs. Rat liver ribonuclease P activity was insensitive to micrococcal nuclease pretreatment. However, the nuclease-treated preparations contained several incompletely degraded RNA species that may have been sufficient to support the ribonuclease P activity. When RNase A was substituted for micrococcal nuclease, the ribonuclease P activity was diminished by greater than 90%, suggesting the requirement for an RNA subunit for activity. 相似文献
106.
5-Aminolevulinic acid (ALA), the common precursor of heme and chlorophyll, can exist in a variety of forms at neutral pH. 13C NMR studies of [3-13C]ALA, [4-13C]ALA, and [5-13C]ALA have been used to demonstrate that the predominant species in solution under physiologic conditions is the ketone. The mole fraction of the hydrate is about 0.6%. To further substantiate the existence of the hydrate, 13C NMR was used to monitor 18O exchange at C4 of [4-13C]ALA with H2, 18O. Confirmation of the existence of the hydrate was achieved through direct observation by 1H NMR. The mole fractions of the enol forms of ALA are each below 0.3%. Although direct observation of the enol forms of ALA has not been achieved, enol formation has been indirectly demonstrated by monitoring hydrogen exchange at the C3 and C5 methylene groups by 1H NMR in D2O. In neutral phosphate buffer, hydrogen exchange occurs readily at both C3 and C5 at a ratio of rates of 1:4. In N-tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid-KOH buffer the hydrogen exchange rates are more than an order of magnitude slower than in phosphate buffer, but the ratio of the exchange rates remains unchanged. The results suggest that phosphate catalyzes enolization at both C3 and C5. To evaluate the role of the C5 substituent in the proton exchange reactions, levulinate and 5-chlorolevulinate (5-CLA) were also monitored for proton exchange at C3 and C5. For levulinate, the hydrogen exchange rates in phosphate buffer are two to three orders of magnitude slower than for ALA, and the rate of hydrogen exchange at C5 is three times slower than hydrogen exchange at C3. The enolization rate at C5 of 5-CLA is identical to ALA while enolization at C3 is about threefold slower for 5-CLA than ALA. These NMR and kinetic studies suggest that under physiologic conditions, ALA rapidly equilibrates between the ketone, the hydrate at C4, and two or more different enols (C3---C4 and C4---C5). The alternative forms of ALA may be biologically significant as active site structures for ALA synthase, glutamate semialdehyde transaminase, or porphobilinogen synthase. These NMR studies have also elucidated the structures of condensation products of ALA which can be formed under physiologic conditions. The alternative forms of ALA, as well as the autocondensation products, may serve as the active toxin in porphyrias characterized by elevated ALA levels (e.g., lead poisoning). 相似文献
107.
N Jayanthi Bai M Ramachandra Pai P Suryanarayana Murthy T A Venkitasubramanian 《Canadian journal of microbiology》1975,21(11):1688-1691
Radiorespirometric studies using glucose labelled at 1, 2, 3-4, and 6 positions and enzymatic studies were conducted to determine the primary pathways of glucose dissimilation in Mycobacterium tuberculosis H37Rv. The pattern of 14CO2 recovery was C3-4 greater than C1 greater than C6 = C2. The Embden-Meyerhof pathway was found to be the predominant pathway for glucose oxidation, operative to the extent of 94%. The pentose phosphate pathway accounted for the remaining 6%. Maximum incorporation of 14C into cellular components was from C2 and C6 labelled glucose. 相似文献
108.
Plant and Soil - A study was conducted on different yield groups of coconut palm (West Coast Tall) to investigate the relationships among root CEC, yield and mono- and divalent cations. The results... 相似文献
109.
Microbial degradation offers an efficient and ecofriendly approach to remove toxicants from the contaminated environments. Botryosphaeria laricina JAS6 and Aspergillus tamarii JAS9 were capable of degrading endosulfan and their metabolites which were isolated through enrichment technique. Both the strains were able to withstand an exposure of 1300 mg/L and showed luxuriant growth at 1000 mg/L of endosulfan. The change in pH in the culture broth was from 6.8 to 3.4 and 3.8 during growth kinetic studies of JAS6 and JAS9 strains, respectively upon biological degradation of endosulfan. The degradation of endosulfan by JAS6 and JAS9 strains were examined by HPLC. The biodegradation rate constant (k) and the initial concentration were reduced by 50% (DT50) which was determined by first and pseudo first order kinetic models. In the present investigation it has been revealed that Botryosphaeria laricina JAS6 and Aspergillus tamarii JAS9 possessing endosulfan degrading capability are being reported for the first time. These findings confirm the degradation of endosulfan by JAS6 and JAS9 strains which were accompanied by significant reduction in the toxicity and could be used as remedial measure in contaminated environments. 相似文献
110.
Kamala de Soyza 《Human genetics》1978,45(2):189-192
Summary Variation of human salivary amylase isoenzymes was investigated by isoelectric focusing on thin-layer polyacrylamide gel. Preliminary studies indicate a genetic polymorphism. 相似文献