Preparation and Characterization of Sealed Inside-Out Peribacteroid Membrane Vesicles from Pisum sativum L. and Glycine max L. Root Nodules by Aqueous Polymer Two-Phase Partitioning

1995 ◽  
Vol 147 (2) ◽  
pp. 175-181 ◽  
Author(s):  
Jens H. Christiansen ◽  
Lis Rosendahl ◽  
Susanne Widell
Keyword(s):  
Root Nodules ◽  
Membrane Vesicles ◽  
Peribacteroid Membrane ◽  
Two Phase ◽  
Phase Partitioning ◽  
Aqueous Polymer ◽  
Pisum Sativum L ◽  
Glycine Max L ◽  
Inside Out

Two-phase partitioning and partial characterization of a collagenase from Penicillium aurantiogriseum URM4622: Application to collagen hydrolysis

2013 ◽  
Vol 75 ◽  
pp. 64-71 ◽  
Author(s):  
Carolina A. Lima ◽  
Augusto C.V. Freitas Júnior ◽  
José L. Lima Filho ◽  
Attilio Converti ◽  
Daniela A. Viana Marques ◽  
...  
Keyword(s):  
Partial Characterization ◽  
Two Phase ◽  
Phase Partitioning ◽  
Penicillium Aurantiogriseum

PREPARATION AND CHARACTERIZATION OF INTACT AND FREE SPORES OF BACILLUS POPILLIAE DUTKY

1967 ◽  
Vol 13 (3) ◽  
pp. 279-285 ◽  
Author(s):  
Grant St. Julian ◽  
Thomas G. Pridham ◽  
Harlow H. Hall
Keyword(s):  
Malachite Green ◽  
Potassium Phosphate ◽  
Staining Technique ◽  
Phase System ◽  
Two Phase ◽  
Aqueous Polymer ◽  
Sonic Treatment ◽  
Bacillus Popilliae ◽  
Almost All

Spores of Bacillus popilliae are enclosed within a large sporangium. In an effort to characterize the spores precisely, a method was developed to free them from their sporangia by sonic vibration. Separation of the free spores from sporangial debris was made by lysozyme treatment, centrifugation, and the Sacks and Alderton aqueous polymer two-phase system. The intact spores are fully refractile; they accept and retain malachite green applied by a modified Wirtz spore-staining technique. The free spores are elongated with rounded ends and measure 1.30–2.25 μ × 0.90–1.40 μ. Outgrowth of intact germinated spores is lowest when heat-activated at 80 °C and highest when heat-activated at 50 °C. Free spores are more heat sensitive than are intact spores, possibly because of damage by the sonic treatment. L-Alanine, adenosine, and glucose separately and in combination do not influence germination of either intact or free spores. Although potassium phosphate somewhat increased germination of intact spores, other salts were ineffective, but almost all salts increased germination of free spores.

scholarly journals Characterization of Ca2+ fluxes in rat liver plasma-membrane vesicles

1988 ◽  
Vol 256 (1) ◽  
pp. 117-124 ◽  
Author(s):  
C Dargemont ◽  
M Hilly ◽  
M Claret ◽  
J P Mauger
Keyword(s):  
Plasma Membrane ◽  
Rat Liver ◽  
Uptake Rate ◽  
Ionic Composition ◽  
Membrane Vesicles ◽  
Plasma Membrane Vesicles ◽  
Microsomal Preparation ◽  
Intact Cells ◽  
Inside Out

Inside-out plasma-membrane vesicles isolated from rat liver [Prpic, Green, Blackmore & Exton (1984) J. Biol. Chem. 259, 1382-1385] accumulated a substantial amount of 45Ca2+ when they were incubated in a medium whose ionic composition and pH mimicked those of cytosol and which contained MgATP. The Vmax of the initial 45Ca2+ uptake rate was 2.9 +/- 0.6 nmol/min per mg and the Km for Ca2+ was 0.50 +/- 0.08 microM. The ATP-dependent 45Ca2+ uptake by inside-out plasma-membrane vesicles was about 20 times more sensitive to saponin than was the ATP-dependent uptake by a microsomal preparation. The 45Ca2+ efflux from the inside-out vesicles, which is equivalent to the Ca2+ influx in intact cells, was increased when the free Ca2+ concentration in the medium was decreased. The Ca2+ antagonists La3+ and Co2+ inhibited the 45Ca2+ efflux from the vesicles. Neomycin stimulated the Ca2+ efflux in the presence of either a high or a low free Ca2+ concentration. These results confirm that polyvalent cations regulate Ca2+ fluxes through the plasma membrane.

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