Determination of histidine α-deaminase in human stratum corneum and its absence in histidinaemia

Abstract

A spectrophotometric method to measure histidine [alpha]-deaminase in the stratum corneum of normal human skin is described. Normal human stratum corneum lacks urocanase. The skin of 2 siblings with histidinemia does not contain any detectable histidine [alpha]-deaminase. This lack of histidine [alpha]-deaminase would appear to be the biochemical abnormality responsible for histidinemia. The distribution of histidine [alpha]-deaminase in several tissues of the guinea pig has also been examined.