Paper Partition Chromatographic Analysis and Microbial Growth Factors: The Vitamin B6 Group

Abstract

A new technique of resolving and identifying the members of the B6 family of growth factors is described. It involves the use of paper partition chromatog-raphy coupled with a microbial indicator. After developing with n-butanol, the strip chromatogram is dried and laid on the surface of a nutrient agar seeded with Saccharomyces carlsbergensis, strain 4228. The nutrient agar contains all factors necessary for the growth of the yeast except the vitamin B6 group. Upon removing the strip chromatogram and incubating overnight, elliptical zones of growth of the organism are seen at intervals along the locus of the strip chromatogram. These zones of growth serve as indicators of the position of the B6 factors on the chromatogram. Using this method of analysis a non-enzymatic reaction of pyridoxal and amino acids to give pyridoxamine has been shown to occur in the cold. A new reaction between pyridoxal and l-cys-teine has been demonstrated. The technique is of value in proving the purity of growth factors. The general technique of paper chromatography and the use of a microbial indicator, in the manner described above, should prove of value in the analysis of other growth factors which exist in nature in > 1 chemically defined form.