Search results for: 141
#141 // To Up
Characterization studies on the membrane-bound adenosine triphosphatase (ATPase) of Azotobacter vinelandii.
The adenosinetriphosphatase (ATPase) (EC 3.6.1.3) activity in Azotobacter vinelandii concentrates in the membranous R3 fraction that is directly associated with Azotobacter electron transport function. Sonically disrupted Azotobacter cells were examined for distribution of ATPase activity and the highest specific activity (and activity units) was consistently found in the particulate R3 membranous fraction which sediments on ultracentrifugation at 144 000 X g for 2 h. When the sonication time interval was increased, the membrane-bound ATPase activity could neither be solubilized nor released into the supernatant fraction. Optimal ATPase activty occurred at pH 8.0; Mg2+ ion when added to the assay was stimulatory. Maximal activity always occurred when the Mg2+:ATP stoichiometry was 1:1 on a molar ratio at the 5 mM concentration level. Sodium and potassium ions had no stimulatory effect. The reaction kinetics were linear for the time intervals studied (0-60 min). The membrane-bound ATPase in the R3 fraction was stimulated 12-fold by treatment wiTH TRypsin, and fractionation studies showed that trypsin treatment did not solubilize ATPase activity off the membranous R3 electron transport fraction. The ATPase was not cold labile and the temperature during the preparation of the R3 fraction had no effect on activity; overnight refrigeration at 4 degrees C, however, resulted in a 25% loss of activity as compared with a 14% loss when the R3 fraction was stored overnight at 25 degrees C. A marked inactivation (although variable, usually about 60%) did occur by overnight freezing (-20 degrees C), and subsequent sonication failed to restore ATPase activity. This indicates that membrane reaggregation (by freezing) was not responsible for ATPase inactivation. The addition of azide, ouabain, 2,4-dinitrophenol, or oligomycin to the assay system resulted in neither inhibition nor stimulation of the ATPase activity. The property of trypsin activation and that ATPase activity is highest in the R3 electron transport fraction suggests that its probable functional role is in coupling of electron transport to oxidative phosphorylation.P Jurtshuk, J E McEntire
2736 related Products with: Characterization studies on the membrane-bound adenosine triphosphatase (ATPase) of Azotobacter vinelandii.
200 ug100ug100μg4 Membranes/Box1 kit1 mL 6 ml Ready-to-use 100ug Lyophilized100ul4 Membranes/BoxRelated Pathways
Contact Us:
Belgium
Voortstraat 49, 1910 Kampenhout BELGIUM
Tel 0032 16 58 90 45 Fax 0032 16 50 90 45
[email protected]
France
9, rue Lagrange, 75005 Paris
Tel 01 43 25 01 50 Fax 01 43 25 01 60
[email protected]
Germany
GENTAUR GmbH
Marienbongard 20
52062 Aachen Deutschland
Tel 0241 40 08 90 86 Fax 0241 55 91 05 36
[email protected]
United Kingdom
GENTAUR Ltd.
Howard Frank Turnberry House
1404-1410 High Road
Whetstone London N20 9BH
Tel 020 3393 8531 Fax 020 8445 9411
[email protected]
Also in
Luxembourg +35220880274
Schweiz Züri +41435006251
Danmark +4569918806
Österreich +43720880899
Česká republika Praha +420246019719
Ireland Dublin +35316526556
Norge Oslo +4721031366
Finland Helsset +358942419041
Sverige Stockholm +46852503438
Ελλάς Αθήνα +302111768494
Magyarország Budapest +3619980547
Poland
GENTAUR Poland Sp. z o.o.
ul. Grunwaldzka 88/A m.2
81-771 Sopot, Poland
Tel 058 710 33 44
Fax 058 710 33 48
[email protected]
skype gentaurpoland
Nederland
GENTAUR Nederland BV
Kuiper 1
5521 DG Eersel Nederland
Tel 0208-080893 Fax 0497-517897
[email protected]
Italy
GENTAUR SRL
IVA IT03841300167
Piazza Giacomo Matteotti, 6, 24122 Bergamo
Tel 02 36 00 65 93 Fax 02 36 00 65 94
[email protected]
Spain
GENTAUR Spain
Tel 0911876558
[email protected]
Bulgaria
GENTAUR Bulgaria
53 Iskar Str. 1191 Kokalyane, Sofia
Sofia 1000
Tel 0035924682280
Fax 0035929830072
[email protected]