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The usefulness of exogenous nicotine as a factor in the induction of morphogenesis in a tobacco tissue culture medium has been demonstrated. Nicotiana rustica callus cell cultures were grown on a modified Murashige and Skoog medium with 2 mg/l indoleacetic acid (IAA) and 0.2 mg/l kinetin (MMS). Root morphogenesis was induced in roller tube callus cell cultures and solid callus cell cultures grown on MMS without kinetin supplemented with 10-100 mg/l nicotine. Optimal nicotine concentration for root induction was 50 mg/l. Other tests using varying combinations of IAA, kinetin and nicotine produced no obvious morphogenesis, although some changes in the amount of callus growth and endogenous protein concentration did correlate with nicotine concentration relative to the presence of IAA and/or kinetin. In liquid MMS medium, 14C-nicotine was primarily incorporated into the protein fraction of cultured cells while primarily incorporated into the cell wall and/or cell membrane fraction of cells cultured on MMS without kinetin in the medium. In MMS without IAA and MMS without both IAA and kinetin, there was incorporation, but to a lesser extent in both the protein and the cell wall and/or cell membrane fractions. [ABSTRACT FROM AUTHOR]

Experiments have shown that salivary gland extracts from marine snail Neptunea antiqua contain an agent with muscarine-like actions; in paper chromatograms the active substance behaved like neurine. In the present investigation a comparison was made between gland extracts and neurine on different biological test objects. Experiments show that the extract of the salivary glands of Neptunea antiqua possesses both muscarinic and nicotinic actions. Experiments suggests that the active agent of the extracts is identical with neurine or a closely related compound. If so the gland should contain as much as about 25 mg of neurine per gram of tissue.

The rate of synthesis of nicotinic acid by partially purified cell extracts of Clostridium butylicum was increased when the substrates L-aspartate and formate were replaced by N-formyl- L-aspartate. Aminopterin (0.2 mM) inhibited the synthesis from L-aspartate and formate, but not from N-formyl-L-aspartate. N-Formyl-D-aspartate did not support the synthesis of nicotinic acid. In the presence of aminopterin, radioactivity from 14C-labelled N-formyl-aspartate was incorporated into nicotinic acid by partially purified cell extracts with only low dilution of the molar specific radioactivity. The pattern of labeling in the synthesised nicotinic acid showed that C-2, 3, 7, and 6 of the nicotinic acid were derived from C-2, 3, 4 and the formyl carbon of N-formyl-aspartic acid. Partially purified extracts of Cl. butylicum synthesised N-formyl-aspartic acid from aspartate and formate and this formylation was inhibited by 0.2 mM aminopterin. [ABSTRACT FROM AUTHOR]