Studies on the Metabolism of Leptospira

Abstract

A factor necessary for the growth of Leptospira canicola is known to exist in animal serum; it is unidentified, and it does not appear to be one of the following: nicotinic acid, thiamin hydrochloride, nicotinic acid amide, riboflavin, vitamin B6 hydrochloride, ascorbic acid. 2. The following substances function as growth-accessory factors, giving marked stimulation to leptospiral growth when used in combination with the unknown factor: nicotinic acid, thiamin hydrochloride, nicotinic acid amide, riboflavin. 3. The view that growth factors inhibit proliferation when used in large concentrations has been corroborated. A possible explanation of the mechanism responsible has been advanced in the case of riboflavin.