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J D Eastin

Publications and source records attributed to J D Eastin.

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A sensitive technique for the rapid measurement of carbon dioxide concentrations.

A method has been developed to measure concentrations of CO(2) in gases rapidly. A gas sample is injected into a flowing carrier gas that passes through an infrared CO(2) analyzer. A strip chart recorded peak response is obtained which is proportional to the CO(2) concentration. A resolution of better than 2 microliters of CO(2) per liter of gas was obtained. Seven to 10 seconds were required for sample analysis once the sample was obtained. Sorghum bicolor plant respiration was determined at different temperatures by measuring CO(2) using this system and by using a conventional system. The correlation between techniques was 0.996, and about the same variation occurred within each method. This technique greatly increased the efficiency of the infrared CO(2) analyzer in our laboratory for use in plant respiration and photosynthetic studies.

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CARBON DIOXIDE FIXATION IN BACILLUS ANTHRACIS.

Eastin, Jerry D. (U.S. Army Chemical Corps, Frederick, Md.) and Curtis B. Thorne. Carbon dioxide fixation in Bacillus anthracis J. Bacteriol. 85:410-417. 1963.-Virulent strains of Bacillus anthracis require a concentration of CO(2) greater than that of the normal atmosphere (air) for the production of capsular material (glutamyl polypeptide); avirulent strains may produce no polypeptide or may produce polypeptide in air. Fixation of C(14)O(2) by each of the three types tested resulted in labeling of aspartic acid, glycine, glutamic acid, succinic acid, and an unidentified organic acid. C(14) was detected in aspartic acid after less than 30 sec of exposure of cells to C(14)O(2). Subsequent flushing of the cells with C(12)O(2) displaced C(14) from aspartic acid but not from the other labeled intermediates. Aspartic acid appears to be closely associated with the primary CO(2)-fixation product, and the data suggest a fairly direct carbon pathway from CO(2) to aspartic acid (oxaloacetic acid) to glutamic acid to glutamyl polypeptide.

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