A RAPID METHOD FOR THE DIFFERENTIATION OF <i>HAEMOPHILUS</i> STRAINS.

Abstract

A rapid and reliable test for demonstrating porphyrin synthesis in Haemophilus strains is described. The method is performed with cell suspensions, and tests the ability of the bacteria to use δ‐aminolaevulinic acid in the biosynthesis of porphobilinogen and porphyrins. The method permits detection of some of the enzyme activities involved in the haemin biosynthetic pathway, and offers as such a more reproducible alternative to the traditional tests for haemin requirement in Haemophilus strains. The method described has been applied to 134 Haemophilus strains and the results applying to 45 strains from culture collections are listed.