Abstract: | The growth of a vitamin K-requiring strain of Bacteroides melaninogenicus was promoted by some postulated and proven biosynthetic precursors of bacterial menaquinones, 1,4-dihydroxy-2-naphthoic acid, shikimic acid, chorismic acid, and 4(2'-carboxyphenyl)-4-oxobutyric acid. Growth of the organism with [2',4-(14)C(2)]-4(2'-carboxy phenyl)-4-oxobutyric acid as the vitamin K replacement gave rise to a mixture of radioactive menaquinone-9 and menaquinone-10; the dilution factor for this incorporation was 1.8. |