Inactivation of adenosine 5'-triphosphate synthesis and reduced-form nicotinamide adenine dinucleotide dehydrogenase activity in Escherichia coli by near-ultraviolet and violet radiations

Abstract

Near-ultraviolet (near-UV) light (300 to 380 nm) is a significant component of sunlight and has a variety of effects on biological systems. The present work is an attempt to identify chromophores (molecular absorbers of light) and targets (critical damaged molecules) for inhibition of adenosine triphosphate (ATP) synthesis in Escherichia coli by near UV. The fluence of 334 nm required for 37% survival of net ATP synthesis (F37) in E. coli AB2463 in succinate medium is 140 kJ/m2. The action spectrum for this inactivation is almost structureless, exhibiting a smooth transition from high efficiency at 313 nm to low efficiency at 405 nm. The action spectrum for inhibition of net ATP synthesis is consistent with the chromophore being either ubiquinone Q-8 or vitamin K2. The fluence required is consistent with ubiquinone Q-8 also being a target molecule. The activity of reduced nicotinamide adenine dinucleotide dehydrogenase in extracts of E. coli B is also inactivated by near UV and shows an F37 of about 40 kJ/m2. The action spectrum for this effect is quite structureless; it shows high efficiency at 313 nm and low efficiency at 435 nm. The data do not suggest a target molecule for this action, although it is possible that ubiquinone Q-8 absorbs the near-UV energy and then passes it on to some other target molecule. The data further indicate that inactivation of the oxidative phosphorylation system is not a primary factor in near-UV-induced growth delay in E. coli.

ULTRAVIOLET (254‐405 nm) ACTION SPECTRUM AND KINETIC STUDIES OF ALANINE UPTAKE IN ESCHERICHIA COLI B/R*

“…and for inhibition of ATP synthesis in a K12 strain of E. coli (F3, = 140kJ/mZ; Lakchaura et al, 1976). Finally, the near-UV action spectrum for inhibition of ATP synthesis (Lakchaura et al, 1976) and the near-UV parts of the glycine and alanine action spectra ( Fig. 4) are quite similar and are consistent with absorption by menaquinone.…”

“…The broken line represents the action spectrum for glycine obtained by Ascenzi and Jagger (1979). and for inhibition of ATP synthesis in a K12 strain of E. coli (F3, = 140kJ/mZ; Lakchaura et al, 1976). Finally, the near-UV action spectrum for inhibition of ATP synthesis (Lakchaura et al, 1976) and the near-UV parts of the glycine and alanine action spectra ( Fig.…”

NEAR ULTRAVIOLET INDUCTION OF GROWTH DELAY STUDIED IN A MENAQUINONE‐DEFICIENT MUTANT OF BACILLUS SUBTILIS

“…aroD163, men-) was derived from strain RBI (men+) and its properties have been described (Farrand and Taber. 1973a;b). It is Men-(<0.005 nmol menaquinone/mg membrane) when grown in tryptose-0.20/, glucose medium lacking shikimic acid.…”

Light-induced inhibition of sporulation in Bacillus licheniformis

“…Tumbling movement and, subsequently, cell paralysis occur when bacteria are exposed to visible light (18). In addition, respiration, penneation, and adenosine 5'-triphosphate (ATP) production can be influenced by light (1,4,13).…”

“…At the present time, neither the primary physiological processes nor the photosensitizing molecules involved in light delay of sporulation have been identified. It is known that exposure of bacteria to light similar to that used in these studies decreases respiration and ATP levels (4,10,13). ATP is required both as an energy source and as a precursor of regulatory nucleotides for sporulation.…”