Cinnamic Acid, an Autoinducer of Its Own Biosynthesis, Is Processed via Hca Enzymes in Photorhabdus luminescens

Abstract

Photorhabdus luminescens, an entomopathogenic bacterium and nematode symbiont, has homologues of the Hca and Mhp enzymes. In Escherichia coli, these enzymes catalyze the degradation of the aromatic compounds 3-phenylpropionate (3PP) and cinnamic acid (CA) and allow the use of 3PP as sole carbon source. P. luminescens is not able to use 3PP and CA as sole carbon sources but can degrade them. Hca dioxygenase is involved in this degradation pathway. P. luminescens synthesizes CA from phenylalanine via a phenylalanine ammonia-lyase (PAL) and degrades it via the not-yet-characterized biosynthetic pathway of 3,5-dihydroxy-4-isopropylstilbene (ST) antibiotic. CA induces its own synthesis by enhancing the expression of the stlA gene that codes for PAL. P. luminescens bacteria release endogenous CA into the medium at the end of exponential growth and then consume it. Hca dioxygenase is involved in the consumption of endogenous CA but is not required for ST production. This suggests that CA is consumed via at least two separate pathways in P. luminescens: the biosynthesis of ST and a pathway involving the Hca and Mhp enzymes.

Transcriptional Analysis of a Photorhabdus sp. Variant Reveals Transcriptional Control of Phenotypic Variation and Multifactorial Pathogenicity in Insects

“…Five genes were more strongly transcribed in VAR* than in TT01␣: mipA, which encodes a protein involved in peptidoglycan synthesis and controlling the growth of the stress-bearing sacculus of Escherichia coli (62); pbgP1, the first gene of an operon encoding the components of an enzymatic pathway involved in arabinose incorporation in the lipid A moiety of lipopolysaccharide and responsible for polymyxin resistance in Salmonella enterica (23,34,35); cat, which encodes a chloramphenicol acetyltransferase (13); ccm, which encodes an internal protein, CcmA, influencing cell shape in Proteus mirabilis (37); and uspG, which encodes a universal stress protein that may, in some cases, be linked to resistance to DNA-damaging agents and to respiratory uncouplers (45). Eight genes were found to be less strongly transcribed in VAR* than in TT01␣: plu1369, which encodes a putative ␤-lactamase (15); ompN, encoding a protein of the porin family responsible for the permeability of Gram-negative bacteria to small, polar molecules (55); sodA and katE (plu3068), which encode the manganese-dependent superoxide dismutase SodA and the catalase KatE, respectively, both of which are involved in the detoxification of reactive oxygen species in Escherichia coli (48); and the hcaE, hcaF, hcaB, and hcaD genes, which belong to an operon encoding the components of a pathway involved in the degradation of 3-phenylpropionate and cinnamic acid and participate in oxidative stress resistance in Photorhabdus (16,17).…”

A Single Promoter Inversion Switches Photorhabdus Between Pathogenic and Mutualistic States

“…The M form produced more cinnamate, a precursor to stilbenes, after 48 hours of growth (fig. S9) likely because of less stilbene synthesis and cinnamate hydrolysis (22, 23). IJ nematodes resumed development and reproduced less on the Mform than on the P form (fig.…”

ASSESSMENT OF AGRICULTURALLY IMPORTANT METABOLITES FROM THE ENTOMOPATHOGENIC BACTERIUM, Photorhabdus temperata M1021

“…In addition, GC-MS analysis of CF revealed a list of compounds including trans-Cinnamic acid, a well-known insecticidal compound (Chalabaev et al, 2008). A number of reports have confirmed a strong larvicidal activity of trans-Cinnamic acid against a diverse group of insects including, Manduca sexta, G. mellonella, Culex quinquefasciatus and Armigeres subalbatus larvae (Eleftherianos et al, 2007;Chalabaev et al, 2008).…”

“…A number of reports have confirmed a strong larvicidal activity of trans-Cinnamic acid against a diverse group of insects including, Manduca sexta, G. mellonella, Culex quinquefasciatus and Armigeres subalbatus larvae (Eleftherianos et al, 2007;Chalabaev et al, 2008). In addition, Seo et al (2012); Salvadori et al (2012) and Eleftherianos et al (2007) investigated that the extracellular compounds i.e., 1,3-dihydroxy-2-(isopropyl)-5-(2-phenylethenyl) benzylideneacetone, proline-tyrosine, acetylated phenylalanineglycine-valine indole, oxindole, cis-cyclo-PY, and phydroxyphenyl propionic produced by Photorhabdus bacteria are involved in the insecticidal activity against different larvae e.g.…”