Growth of Escherichia coli on Medium Containing Glycine Increases Transformation Efficiency

Abstract

a flophemesyl derivative. In the latter spectrum, an allylic cleavage between the first two double bonds is reflected by the ion at m/z 392, and allylic and vinylic leavages between the second and third double bonds re reflected by ions at m/z 432 and 420. These data ield useful information about double-bond location n USFAs (8), and structurally informative fragment ons in these spectra are produced by cleavage of onds remote from the charge site on the flophemesyl ster moiety. In conclusion, the present method is described in hich the compounds of saturated and monoor polynsaturated FAs are derivatized to their respective ophemesyl esters. The flophemesyl derivatives are eadily prepared, have excellent chromatographic roperties, and in complex mixtures, can distinguish etween the saturation and the degree of unsaturation. lso, concerning the identification of SFAs in several atrices, it is an especially advantageous method for etection and characterization. Because the M-15 ion s the most intense, the use of these derivatives faciliates the measurement of the molecular weight of trace mounts of unknown acids with much greater confience than is possible when using other derivatives.