Bioluminescence of the insect pathogen Xenorhabdus luminescens.

AUTOR(ES)

Schmidt, T M

RESUMO

Luminescence of batch cultures of Xenorhabdus luminescens was maximal when cultures approached stationary phase; the onset of in vivo luminescence coincided with a burst of synthesis of bacterial luciferase, the enzyme responsible for luminescence. Expression of luciferase was aldehyde limited at all stages of growth, although more so during the preinduction phase. Luciferase was purified from cultures of X. luminescens Hm to a specific activity of 4.6 x 10(13) guanta/s per mg of protein and found to be similar to other bacterial luciferases. The Xenorhabdus luciferase consisted of two subunits with approximate molecular masses of 39 and 42 kilodaltons. A third protein with a molecular mass of 24 kilodaltons copurified with luciferase, and in its presence, either NADH or NADPH was effective in stimulating luminescence, indicating that this protein is an NAD(P)H oxidoreductase. Luciferases from two other luminous bacteria, Vibrio harveyii (B392) and Vibrio cholerae (L85), were partially purified, and their subunits were separated in 5 M urea and tested for complementation with the subunits prepared from X. luminescens Hb. Positive complementation was seen with luciferase subunits among all three species. The slow decay kinetics of the Xenorhabdus luciferase were attributed to the alpha subunit.

Documentos Relacionados

• Cloning, organization, and expression of the bioluminescence genes of Xenorhabdus luminescens.
• Characterization of form variants of Xenorhabdus luminescens.
• Characterization of an Extracellular Protease from the Insect Pathogen Xenorhabdus luminescens
• Immobilization of Escherichia coli expressing the lux genes of Xenorhabdus luminescens.
• Identification of an anthraquinone pigment and a hydroxystilbene antibiotic from Xenorhabdus luminescens.