Vibrio harveyi bioluminescence plays a role in stimulation of DNA repair We would like to dedicate this paper to the memory of Karol Taylor, who introduced V. harveyi projects to our laboratories.

Abstract

Although the genetics and biochemistry of bacterial luminescence have been investigated extensively, the biological role of this phenomenon remains unclear. Here it is shown that luxA, luxB and luxD mutants (unable to emit light) of the marine bacterium Vibrio harveyi are significantly more sensitive to UV irradiation when cultivated in the dark after irradiation than when cultivated under a white fluorescent lamp. This difference was much less pronounced in the wild-type (luminescent) V. harveyi strain. Survival of UVirradiated Escherichia coli wild-type cells depended on subsequent cultivation conditions (in the dark or in the presence of external light). However, after UV irradiation, the percentage of surviving E. coli cells that bear V. harveyi genes responsible for luminescence was significantly higher than that of nonluminescent E. coli, irrespective of the subsequent cultivation conditions. Moreover, it is demonstrated that luminescence of V. harveyi can be stimulated by UV irradiation even in diluted cultures, under conditions when light emission by these bacteria is normally impaired due to quorum sensing regulation. It is proposed that luminescent bacteria have an internal source of light which could be used in DNA repair by a photoreactivation process. Therefore, production of internal light ensuring effective DNA repair seems to be at least one of the biological functions of bacterial luminescence.

Identification of a Gene Cluster for the Formation of Extracellular Polysaccharide Precursors in the Chemolithoautotroph Acidithiobacillus ferrooxidans

“…Analysis of the lux A-like gene. The predicted protein potentially derived from lux A-like exhibits similarity with the LuxA family of bacterial luciferase-like monooxygenases and contains the pfam00296 domain characteristic of this family (6,31). It also contains COG2141, characteristic of the coenzyme An alternative hypothesis is that lux A-like encodes the missing GalT function typically found in the gal operon but not detected in the A. ferrooxidans gal operon.…”

Mutations in the lux Operon of Natural Dark Mutants in the Genus Vibrio

“…It is generally assumed that the preservation of gene sequences is the result of positive selection, but selection in the lux operon has long been the subject of debate (2,4,5,23,34). Several Vibrio and Photobacterium strains trade light for nutrients while participating in symbiotic relationships with various fish and/or squid species (7,23,30,31).…”

Evolution of symbiosis in the Vibrionaceae: a combined approach using molecules and physiology

“…Members of this family are globally important due to their prevalence in numerous ecological niches. Many species of the Vibrionaceae possess the ability to bioluminesce via the lux operon, although its biological role in bacterial cells remains unknown (Czyż et al, 2000). Many of these luminescent species form symbiotic relationships, both pathogenic and cooperative, with marine organisms.…”