Carnosinase deficiency

Hydrolysis of carnosine to p-alanine and L-histidine is catalyzed by carnosinase. The heritable disorder carnosinase deficiency is characterized by carnosinuria. 

Serum carnosinase deficiency. This relatively rare disease described in children becomes apparent as camosinemia and camosinurea (increased camosine level in blood and urea). This is caused by very low activity of semm carnosinase which in half of the cases analyzed was characterized by sufficiently elevated Km for substrates [108]. From 23 sick children (belonging to different families) 14 were found to have neurological lesions, myoclonal convulsions, mental retardation at the same time, the correlation between intensity of neurological disorders and residual activity of carnosinase was not found [108]. 

A rare inborn error of metabolism in which there is a deficiency of the enzyme carnosinase which converts carnosine to -alanine and histidine. Mental retardation is a clinical feature. 

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