. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. PANTOTHENIC ACID AND GROWTH ()!• PROTOZOA 87 Some other, still unknown, substance is cleficic'iit in this incomplete protein. Scries ir-—Colpidinin striaiuni It was shown in a previous investigation (Hall and Elliott, MSS) that by adding small quantities of yeast extract to gliadin that growth could be maintained indefinitely ; likewise, by adding a small amount of yeast extract to zein, together with lysine which is lacking in this protein, indefinite growth could be maintained. This indicated that some substance in yeast w
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. PANTOTHENIC ACID AND GROWTH ()!• PROTOZOA 87 Some other, still unknown, substance is cleficic'iit in this incomplete protein. Scries ir-—Colpidinin striaiuni It was shown in a previous investigation (Hall and Elliott, MSS) that by adding small quantities of yeast extract to gliadin that growth could be maintained indefinitely ; likewise, by adding a small amount of yeast extract to zein, together with lysine which is lacking in this protein, indefinite growth could be maintained. This indicated that some substance in yeast was essential for the growth of Colpidiujn. Perhaps this substance was pantothenic acid? The following series of experiments was devised to test this point. 8. 45 FIG. 3. Series III. Concentration of ciliates in thousands per cubic centi- meter plotted against pH. The solid line indicates growth in the gelatin control; the broken line, growth with pantothenic acid. The procedure was slightly different from that employed in the fore- going series. The basic medium consisted of 1 per cent protein (zein, gliadin, or gelatin) and per cent KH2PO4 in distilled water. The pH was set at in all tubes since previous experiments had demon- strated that acceleration occurred in that range. To 6 tubes containing zein (8 cc. each) lysine was added (1 cc. of per cent stock solu- tion) ; to each of 6 others, was added 1 cc. of pantothenic acid (con- centration identical with that used in Series I) ; and to a third set of 6 tubes was added both lysine and pantothenic acid. In a similar manner lysine and pantothenic acid were added to 3 sets (6 each) of tubes. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Marine Biological Laboratory (Woods Hole, Mass. ); Marine Biological Laboratory (Woods Ho
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
