Specificity in V Factor Activity

Lwoff and Lwoff (221) found that H. parainfluenzac was imable to use nicotinic acid, nicotinamide, adenylic acid (yeast or muscle), the diethylamide of nicotinic acidj or o-dihydropropyl nicotinamide. Schlenk and Gingrich (327) extended this, testing intermediate degradation products of cozymase. The following results were obtained  

Minimum cone, for detectable srowth effect mtdium 

The observations of Bass, et al. (11), that preparations of beef and horse liver catalase could supply V factor activity for H. influenzae,-were interpreted by them as real, and not due to the presence of phospho-pyridine nucleotides as impurity, mainly on the results of comparative heat stability experiments. This interpretation is not yet acceptable in view of Schlenk and Gingrich s findings (327, 103b) that nicotinamide nucleoside has high Y factor activity. A physiological function of catalase activity as replacing V factor activity was excluded by showing that destruction of catalase activity did not destroy the apparent V factor activity of the preparations. A cautious attitude to these observations is necessary until more is known about the exact composition of the catalase preparations used. 

Differences of Synthetic A hilities of Bacteria in Relation to Phosphopyridine Nucleotides 

When some species of micro-organisms require a part, and others the whole, of the phosphopyridine nucleotide molecule, the simplest deduction 

---