Difference absorption spectrum of cytochrome c oxidase in the presence of acephate (N-acetvl O,S-dimethyl thiophosphoramide)

1983 ◽  
Vol 17 (1-2) ◽  
pp. 85-88 ◽  
Author(s):  
Mitsuru Ando ◽  
Kunimitsu Wakamatsu
Keyword(s):  
Absorption Spectrum ◽  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Difference Absorption Spectrum ◽  
Difference Absorption

scholarly journals Pulsed cytochrome c oxidase from the thermophilic bacterium PS3

1984 ◽  
Vol 223 (3) ◽  
pp. 809-813 ◽  
Author(s):  
N Sone ◽  
A Naqui ◽  
C Kumar ◽  
B Chance
Keyword(s):  
Enzyme Activity ◽  
Absorption Spectrum ◽  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Oxidase Activity ◽  
Thermophilic Bacterium ◽  
Decay Process ◽  
Mitochondrial Enzyme ◽  
Bovine Heart ◽  
Enhanced Activity

A caa3-type terminal cytochrome c oxidase (EC 1.9.3.1) from the thermophilic bacterium PS3 containing three subunits showed conversion from resting into pulsed form. Upon pulsing (reduction and re-oxidation), the cytochrome c oxidase activity increased over 10-fold. This enhanced activity of the pulsed enzyme gradually decayed. Addition of phospholipids, necessary for the enzyme activity, did not affect this decay process. Small changes in the absorption spectrum were observed for the resting-into-pulsed transition and for H2O2 ligation to the pulsed enzyme. The e.p.r. spectrum of the resting enzyme was very similar to that of mitochondrial enzyme, but the transient g = 5, 1.78 and 1.69 set of e.p.r. signals, associated with the pulsed bovine heart oxidase, were not observed in the case of pulsed bacterium-PS3 enzyme.

scholarly journals The Estimation of Cytochrome C Oxidase in Animal Tissues

1948 ◽  
Vol 1 (1) ◽  
pp. 139 ◽  
Author(s):  
TAF Quinlan-Watson ◽  
DW Dewey
Keyword(s):  
Absorption Spectrum ◽  
Cytochrome C ◽  
Oxygen Uptake ◽  
Cytochrome Oxidase ◽  
Cytochrome C Oxidase ◽  
Rate Of Change ◽  
Animal Tissues ◽  
Large Excess ◽  
Spectrophotometric Measurement

Method for the stimation of cytochrom, c oxidase are dependent eitherupon the change which occurs in the absorption spectrum of cytochrome c whenit is oxidized by cytochrome oxidase (Altschul, Abrams, and Hogness 1939;Albaum, Tepperman and Bodansky 1946a, 1946b), or upon the absorption ofgaseous oxyen by, a !!ysten. which consists essentially of a preparation of cytochromeoX~,�Jase in the. pz:esence of a large excess of reduced cytochrome c. Ineither case, it is the rate of oxidation of reduced cytochrome c which is es~imated;in the former by spectrophotometric measurement of the rate of change in lighttransmission . at two different wllyelengths; and, in the latter by manometricestimation of the rate of oxygen uptake (Keilin and Hartree 1938; Stotz 1939;Schneider and Potter 1943). The rate of oxidation of the reduced cytochrome c . , ,"is proportional, under. certain, conditions, to the amount of cytochrome oxidasepresent, apd so. can be used as a measure of ~he activity' of cytochrome oxidase .itself.

scholarly journals DERIVED PHOTOSENSITIVE PIGMENTS FROM INVERTEBRATE EYES

1943 ◽  
Vol 26 (4) ◽  
pp. 361-367 ◽  
Author(s):  
Alfred F. Bliss
Keyword(s):  
Absorption Spectrum ◽  
Spectral Sensitivity ◽  
Blue Crab ◽  
Horseshoe Crab ◽  
Light Sensitivity ◽  
Red Pigment ◽  
Difference Absorption Spectrum ◽  
Light Stability ◽  
The Difference ◽  
Difference Absorption

The red pigment in the eyes of the squid, blue crab, and horseshoe crab becomes photosensitive when treated with formalin, and bleaches in the light. The resulting change in density is approximately symmetrical around a maximum at 480 mµ in the blue green. This difference absorption spectrum is in rough agreement with the spectral sensitivity of the cephalopod eye and differs only slightly from the difference absorption spectrum of vertebrate visual purple. The formalin-sensitized pigment is not melanoid. Its bleaching in squid retinas releases large quantities of retinene. It is suggested that the light sensitivity of the normal squid photopigment may be independent of its light stability.

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