. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. I 500 650 550 600 650 500 550 600 WAVELENGTH, m/i WAVELENGTH, m/i FIGURE 1. Spectral absorption curves of colors obtained with the Dische reaction. (A) Whole egg homogenate of S. purpitrutns; (B) top layer and (C) combined pellet and clear layer obtained after differential centrifugation of homogenates of S. pitrpitratiis eggs (see text) ; (D) sperm of L. pictus; (E) pre-purified and alpha amylase-treated extract from eggs of L. pic tits; (F) deoxyadenosine standard. layer the following values (in micrograms
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. I 500 650 550 600 650 500 550 600 WAVELENGTH, m/i WAVELENGTH, m/i FIGURE 1. Spectral absorption curves of colors obtained with the Dische reaction. (A) Whole egg homogenate of S. purpitrutns; (B) top layer and (C) combined pellet and clear layer obtained after differential centrifugation of homogenates of S. pitrpitratiis eggs (see text) ; (D) sperm of L. pictus; (E) pre-purified and alpha amylase-treated extract from eggs of L. pic tits; (F) deoxyadenosine standard. layer the following values (in micrograms "DXA" per million eggs) were obtained: , , , ; av. , , ; av. .9. purpuratus L. pictus For the sperm the values were as follows : .V. purpuratus L. , ; av. , ; av. The spectrum of the Dische-reacted combined pellet and clear layer (curve C of Figure 1J is somewhat less abnormal than that of the other preparations. After exploration of a number of methods of disposing of the interfering mate- rial the use of alpha amylase proved effective. Preparations that are obtained by a single buoyant density separation show a turbid polysaccharide layer (see section 3) at the same level of the tube where the DXA is located. \Yhen this fraction, after it is precipitated with alcohol and redissolved, is treated with alpha amylase, as described in section 3, it gives a typical deoxyribose spectrum in the Dische reaction, as illustrated in curve E of Figure 1. By this procedure the DXA values obtained for the two species were: L. pictus S. purpuratus These are similar to the values obtained by UV absorption measurements on puri- fied DXA as described below. (2) Evidence against "trapping" of DNA in the top la\cr In order to examine the possibility that DXA might be trapped in the top layer that forms upon centrifugation of homogenates in the CsCl solutions, use was. Please note that these
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
