title: Bioluminescent enzyme assay for the indication of plant stress in enclosed life support systems.
abstract: The application of bioluminescent sensors for monitoring key metabolites and enzymes that are indicators of stress in plants is demonstrated. The sensitivity of bioluminescent assay for NAD(P)H and NAD(P)(+) was about 0.5 and 1 nmol, respectively. The levels of NAD(P)H and NAD(P)(+) in radish (Raphanus sativus) root extracts from controls and from stress-induced conditions were compared. To induce environmental stress, the plants were grown in enclosed environmental chambers with low pressure (9 or 32 kPa), high humidity (>80%) and low oxygen partial pressure (down to 3.3-6.5 kPa). The concentrations of NAD(P)(+) and NAD(P)H in plants varied under stress conditions. Decreasing both total pressure from 101.5 to 32 or 9 kPa and partial pressure of oxygen increased the ratio of NAD(P)(+) /NAD(P)H from 0.2 to 4 or 6, respectively. The increase in this ratio suggests that plants are undergoing stress in these hypobaric environments. The developed bioluminescent assay for quantification of pyridine nucleotides in plant tissues is rapid, low-cost and easily performed.
authors.affiliation: Siberian Federal University, Krasnoyarsk, 660041, Russia.
authors.forename: Valentina
authors.initials: V
authors.lastname: Kratasyuk
authors.forename: Elena
authors.initials: E
authors.lastname: Esimbekova
authors.forename: Melanie
authors.initials: M
authors.lastname: Correll
authors.forename: Ray
authors.initials: R
authors.lastname: Bucklin
mesh_terms: D049449:Luminescence; D009249:NADP / Q000378:metabolism; D031224:Raphanus / Q000378:metabolism / Q000502:physiology*; D013312:Stress, Physiological
chemical_list: D009249:NADP