Urea
hydrolysis
Esculin
hydrolysis
DN-ase
Indole
production
Phenylalanine
deaminase
Trehalose
fermentation
D-mannitol
fermentation
P. asymbiotica subsp.
asymbiotica
+
+
-
-
-
[+]
-
P. asymbiotica subsp.
australis
+
-
+
-
-
-
-
P. luminescens subsp.
luminescens
[-]
+
-
+
-
[+]
d
P. luminescens subsp.
akhurstii
d
+
-
d
-
[+]
+
P. luminescens subsp.
laumondii
[+]
+
+
+
d
[+]
-
P. temperata
d
[+]
+
[-]
[+]
[+]
[-]
Legend:  + positive 90-100%, - negative 90-100%, [+] positive 75-89%, [-] negative 75-89%, d positive 25-74% of strains
Genus Photorhabdus
Taxonomy
Morphology
Cultural characteristics
Biochemical characters
Ecology
Pathogenicity
References
Phylum Proteobacteria, Class Gammaproteobacteria, Order Enterobacteriales, Family Enterobacteriaceae, Genus Photorhabdus,
- Photorhabdus asymbiotica subsp. asymbiotica (Fischer-Le Saux et al. 1999) Akhurst et al. 2004,
- Photorhabdus asymbiotica subsp. australis  Akhurst et al. 2004,
- Photorhabdus luminescens - type species of the genus, basonym: Xenorhabdus luminescens Thomas and Poinar 1979, this
species has been divided into subspecies:
-
Photorhabdus luminescens subsp. akhurstii Fischer-Le Saux et al. 1999,
-
Photorhabdus luminescens subsp. caribbeanensis * Tailliez et al. 2010,
-
Photorhabdus luminescens subsp. hainanensis * Tailliez et al. 2010,
-
Photorhabdus luminescens subsp. kayaii * Hazir et al. 2004,
-
Photorhabdus luminescens subsp. kleinii * An and Grewal 2011,
-
Photorhabdus luminescens subsp. laumondii Fischer-Le Saux et al. 1999,
-
Photorhabdus luminescens subsp. luminescens (Thomas and Poinar 1979) Fischer-Le Saux et al. 1999,
-
Photorhabdus temperata Fischer-Le Saux et al. 1999, this species has been divided into subspecies:
-
Photorhabdus temperata subsp. cinerea * Toth and Lakatos 2008,
-
Photorhabdus temperata subsp. khanii * Tailliez et al. 2010,
-
Photorhabdus temperata subsp. stackebrandtii * An and Grewal 2011,
-
Photorhabdus temperata subsp. tasmaniensis * Tailliez et al. 2010,
-
Photorhabdus temperata subsp. temperata (Fischer-Le Saux et al. 1999) Tóth and Lakatos 2008,
-
Photorhabdus temperata subsp. thracensis * (Hazir et al. 2004) Tailliez et al. 2010.

Species marked with * are not included in ABIS database.
Gram-negative rods, 2-6 x 0-5-1.4 µm. Motile by peritrichous flagella. Produce a faint
glow. The suggested mode of light production is that cell uses the luciferase pathway
as a terminal oxidase, allowing it to continue aerobic metabolism in low oxygen
conditions.
Polimorph, yellow, brown or nonpigmented colonies. Bioluminescent. Facultatively
anaerobic, optimum growth temperature 28 ºC. Maximum temperature for growth in
nutrient broth may be 36 to 40 ºC. Annular hemolysis observed on sheep-blood agar
and, in some strains, on horse-blood agar.
Photorhabdus asymbiotica subsp. asymbiotica & subsp. australis were isolated from
human clinical specimens in Australia.
P. luminescens & P. temperata were isolated
from nematodes from the genus Heterorhabditis or from insects infected with these
nematodes.
Symbiotic bacteria of entomopathogenic nematodes or in the infected insects.
Together,
Photorhabdus luminescens and their nematode host infect and kill insects
that are used during their reproductive cycles. Toxicity for insects is caused by a
series of antimicrobial end products that are excreted by the symbiont during the
multiplication of the nematodes in the insects hosts.
Some isolates from human wounds.
Some strains may have antibacterial or antifungal activity.
  1. J. G. Holt et al., 1994. Facultatively Anaerobic Gram-Negative Rods. Subgroup 1. Family Enterobacteriaceae. In: Begey’s Manual of
    Determinative Bacteriology, 9th-edition, Williams & Wilkins, pp 175-189.
  2. Bleakley B. & Nealson K.H.: Characterization of primary and secondary forms of Xenorhabdus luminescens strain Hm, 1988,
    FEMS Microbiol. Ecol. 53: 241-250.
  3. Boemare N.E., Akhurst R.J., Mourant R.G.: DNA relatedness between Xenorhabdus spp. (Enterobacteriaceae), symbiotic bacteria
    of entomopathogenic nematodes, and a proposal to transfer Xenorhabdus luminescens to a new genus, Photorhabdus gen. nov,  
    1993, International Journal of Systematic Bacteriology. 43:(2) 249-255.
  4. R. J. Akhurst, N. E. Boemare, P. H. Janssen, M. M. Peel, D. A. Alfredson, and C. E. Beard. Taxonomy of Australian clinical isolates
    of the genus Photorhabdus and proposal of Photorhabdus asymbiotica subsp. asymbiotica subsp. nov. and P. asymbiotica
    subsp. australis subsp. nov. Int J Syst Evol Microbiol July 2004 54:1301-1310.
  5. Marion Fischer-Le Saux, Veronique Viallard, Brigitte Brunel, Phillippe Normand, and Noel E. Boemare. Polyphasic classification of
    the genus Photorhabdus and proposal of new taxa: P. luminescens subsp. luminescens subsp. nov., P. luminescens subsp.
    akhurstii subsp. nov., P. luminescens subsp. laumondii subsp. nov., P. temperata sp. nov., P. temperata subsp. temperata subsp.
    nov. and P. asymbiotica sp. nov. IJSEM October 1999 49:1645-1656.
  6. Don J. Brenner and J.J. Farmer III, 2001. Family I. Enterobacteriaceae. In:  Bergey’s Manual of Systematic Bacteriology, Second
    edition, Vol two, part B, George M. Garrity (Editor-in-Chief), pp 587-897.
Positive results for catalase, gelatin hydrolysis, acid production from: glucose (without gas production), glycerol, maltose, fructose,
ribose & D-mannose.

Negative results for oxidase, ONPG, arginine dihydrolase, lysine decarboxylase, ornithine decarboxylase, H
2S production,
Voges-Proskauer reaction, growth on KCN media, nitrate reduction, mathyl red, acid production from: adonitol, lactose, D-sorbitol,
L-rhamnose, sucrose, melibiose, L-arabinose, cellobiose, dulcitol, alpha-methyl-D-glucoside, raffinose, salicin & D-xylose.
(c) Costin Stoica
Antibiogram
Encyclopedia
Culture media
Biochemical tests
Stainings
Images
Movies
Articles
Identification
Software
R E G N U M
PROKARYOTAE
Differential characters of the species & subspecies:
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