. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. GLUTATHIONE AND ANAEROBIOSIS 337. -0 4 volts FIGURE 3. Polarograms of the same hind-gut sample from Cryptoccrcus: (A) untreated, (B) following pure oxygen passage ten minutes, (C) following a 20-minute additional period of pure oxygen passage, and (D) nitrogen gas passage, 40 minutes (sensitivity X 5; pH approx- imately at start). to a more nega- potential shifted back to a more negative reading. Shift of --E tive position was first viewed as a result of alkalinity increase following a CO blozv-off. But, upon further con
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. GLUTATHIONE AND ANAEROBIOSIS 337. -0 4 volts FIGURE 3. Polarograms of the same hind-gut sample from Cryptoccrcus: (A) untreated, (B) following pure oxygen passage ten minutes, (C) following a 20-minute additional period of pure oxygen passage, and (D) nitrogen gas passage, 40 minutes (sensitivity X 5; pH approx- imately at start). to a more nega- potential shifted back to a more negative reading. Shift of --E tive position was first viewed as a result of alkalinity increase following a CO blozv-off. But, upon further consideration, oxygen passage would also be expected to achieve the same effect, and does not. A change in pH, nevertheless, first in one direction and then the other, appears responsible for corresponding shifts in reduction potential. Curves B and C, Figure 3, show a progressive reduction in GSH concentration for one sample following contact with pure oxygen. Curve A represents the sample's GSH level prior to oxygen exposure. Curve A differs from the previous experiment's unexposed sample (Curve A, Fig. 2), registering approximately //a more GSH and a slightly higher pH, judging from the more negative E ^ position. Curve B, Figure 3, was recorded following oxygen passage for ten minutes. From a comparison of microampere readings between Curve A (original concentra- tion) and Curve B, estimated GSH drop was 50%. Curve C, Figure 3, was recorded following oxygen passage lasting 20 additional minutes, in which the GSH level was further reduced. Even under these extreme conditions, in a sample less than ml., it was not possible to demonstrate the presence of dissolved oxygen. Continuing with the same sample, nitrogen passage — following oxygen exposure of the extreme intensity just described — failed unaccountably to demonstrate the. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
