Abstract
Recently, we showed that Paramecium primaurelia synthesizes molecules functionally related to the cholinergic system and involved in modulating cell-cell interactions leading to the sexual process of conjugation. It is known that nitric oxide (NO) plays a role in regulating the release of transmitter molecules, such as acetylcholine, and that the NO biosynthetic enzyme, nitric oxide synthase (NOS), shows nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) activity. In this work, we detected the presence of NADPH-d activity in P. primaurelia. We characterized this activity histochemically by examining its specificity for β-NADPH and α-NADH co-substrates, and sensitivity both to variations in chemico-physical parameters and to inhibitors of enzymes showing NADPH-d activity. Molecules immunologically related to NOS were recognized by the anti-rat brain NOS (bNOS) antibody. Moreover, bNOS immunoreactivity and NADPH-d activity sites were found to be co-localized. The non-denaturing electrophoresis, followed by exposure to β-NADPH or α-NADH co-substrates, revealed the presence of a band of apparent molecular mass of about 124 kDa or a band of apparent molecular mass of about 175 kDa, respectively. In immunoblot experiments, the bNOS antibody recognized a single band of apparent molecular mass of about 123 kDa.
Original language | English |
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Pages (from-to) | 201-208 |
Number of pages | 8 |
Journal | European Journal of Protistology |
Volume | 42 |
Issue number | 3 |
DOIs | |
Publication status | Published - Sep 29 2006 |
Keywords
- Ciliates
- NADPH-diaphorase activity
- Nitric oxide synthase immunoreactivity
- Paramecium
ASJC Scopus subject areas
- Agricultural and Biological Sciences(all)
- Agricultural and Biological Sciences (miscellaneous)
- Microbiology