The Growth-Promoting Properties of Quinic Acid

Evidence is accumulating that there is a common metabolic precursor to many of the benzene ring derivatives found in living organisms [1-4]. Recent work by Davis' and Tatum4 indicates that one such precursor is the naturally occurring shikimic acid (Fig. 1) since this compound serves as a growth factor for certain mutants of Escherichia coli [3] and Neurospora [4] which otherwise require a combination of tyrosine, phenylalanine, tryptophan and p-aminobenzoic acid for growth. These mutants cannot utilize the closely related, naturally occurring quinic acid (Fig. 1) as a substitute for any of their requirements. [3, 4] In an earlier investigation of quinic acid and shikimic acid, Fischer and Dangschat [5, 6] showed that quinic acid is chemically convertible to shikimic acid and that the latter is convertible to glucodesonic acid. They pointed to the possibility that these compounds are formed directly from glucose. For these reasons the growth-promoting properties of quinic acid and shikimic acid were reinvestigated with a Neurospora mutant, C-86, which is capable of utilizing a variety of aromatic compounds for growth [2, 7, 8]. Table 1 gives a list of compounds utilized by C-86 together with those utilized by several other mutants used in this investigation [2, 7-9].