Previous Article | Next Article 
Appl Environ Microbiol, April 1998, p. 1188-1193, Vol. 64, No. 4
0099-2240/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.
Phase Variation in Xenorhabdus
nematophilus
Antonia
Volgyi,1,2
Andras
Fodor,2
Attila
Szentirmai,3 and
Steven
Forst1,*
Department of Biological Sciences, University
of Wisconsin, Milwaukee, Wisconsin 53201,1
and
Department of Genetics, Eotvos Lorand University,
Budapest,2 and
Department of
Microbiology, Kossuth Lajos University,
Debrecen,3 Hungary
Received 15 October 1997/Accepted 5 January 1998
Xenorhabdus nematophilus is a symbiotic bacterium that
inhabits the intestine of entomopathogenic nematodes. The
bacterium-nematode symbiotic pair is pathogenic for larval-stage
insects. The phase I cell type is the form of the bacterium normally
associated with the nematode. A variant cell type, referred to as phase
II, can form spontaneously under stationary-phase conditions. Phase II cells do not elaborate products normally associated with the phase I
cell type. To better define phase variation in X. nematophilus, several strains (19061, AN6, F1, N2-4) of this
bacterium were analyzed for new phenotypic traits. An analysis of
pathogenicity in Manduca sexta larvae revealed that the
phase II form of AN6 (AN6/II) was significantly less virulent than the
phase I form (AN6/I). The variant form of N2-4 was also avirulent. On
the other hand, F1/II and 19061/II were as virulent as the respective
phase I cells. Strain 19061/II was found to be motile, and AN6/II
regained motility when the bacteria were grown in low-osmolarity
medium. In contrast, F1/II remained nonmotile. The phase II cells did not produce the outer membrane protein, OpnB, that is normally induced
during the stationary phase. Both phase I and phase II cells were able
to support nematode growth and development. These findings indicate
that while certain phenotypic traits are common to all phase II cells,
other characteristics, such as virulence and motility, are variable and
can be influenced by environmental conditions.
*
Corresponding author. Mailing address: Department of
Biological Sciences, University of Wisconsin, P.O. Box 413, Milwaukee, WI 53201. Phone: (414) 229-6373. Fax: (414) 229-3926. E-mail: sforst{at}csd.uwm.edu.
This article has been cited by other articles:
-
Drace, K., Darby, C.
(2008). The hmsHFRS Operon of Xenorhabdus nematophila Is Required for Biofilm Attachment to Caenorhabditis elegans. Appl. Environ. Microbiol.
74: 4509-4515
[Abstract]
[Full Text]
-
Goetsch, M., Owen, H., Goldman, B., Forst, S.
(2006). Analysis of the PixA Inclusion Body Protein of Xenorhabdus nematophila.. J. Bacteriol.
188: 2706-2710
[Abstract]
[Full Text]
-
Orchard, S. S., Goodrich-Blair, H.
(2005). Pyrimidine Nucleoside Salvage Confers an Advantage to Xenorhabdus nematophila in Its Host Interactions. Appl. Environ. Microbiol.
71: 6254-6259
[Abstract]
[Full Text]
-
Orchard, S. S., Goodrich-Blair, H.
(2004). Identification and Functional Characterization of a Xenorhabdus nematophila Oligopeptide Permease. Appl. Environ. Microbiol.
70: 5621-5627
[Abstract]
[Full Text]
-
Meslet-Cladiere, L. M., Pimenta, A., Duchaud, E., Holland, I. B., Blight, M. A.
(2004). In Vivo Expression of the Mannose-Resistant Fimbriae of Photorhabdus temperata K122 during Insect Infection. J. Bacteriol.
186: 611-622
[Abstract]
[Full Text]
-
Martens, E. C., Heungens, K., Goodrich-Blair, H.
(2003). Early Colonization Events in the Mutualistic Association between Steinernema carpocapsae Nematodes and Xenorhabdus nematophila Bacteria. J. Bacteriol.
185: 3147-3154
[Abstract]
[Full Text]
-
Zhou, X., Kaya, H. K., Heungens, K., Goodrich-Blair, H.
(2002). Response of Ants to a Deterrent Factor(s) Produced by the Symbiotic Bacteria of Entomopathogenic Nematodes. Appl. Environ. Microbiol.
68: 6202-6209
[Abstract]
[Full Text]
-
Vivas, E. I., Goodrich-Blair, H.
(2001). Xenorhabdus nematophilus as a Model for Host-Bacterium Interactions: rpoS Is Necessary for Mutualism with Nematodes. J. Bacteriol.
183: 4687-4693
[Abstract]
[Full Text]
-
Brillard, J., Ribeiro, C., Boemare, N., Brehélin, M., Givaudan, A.
(2001). Two Distinct Hemolytic Activities in Xenorhabdus nematophila Are Active against Immunocompetent Insect Cells. Appl. Environ. Microbiol.
67: 2515-2525
[Abstract]
[Full Text]
-
Volgyi, A., Fodor, A., Forst, S.
(2000). Inactivation of a Novel Gene Produces a Phenotypic Variant Cell and Affects the Symbiotic Behavior of Xenorhabdus nematophilus. Appl. Environ. Microbiol.
66: 1622-1628
[Abstract]
[Full Text]
-
Givaudan, A., Lanois, A.
(2000). flhDC, the Flagellar Master Operon of Xenorhabdus nematophilus: Requirement for Motility, Lipolysis, Extracellular Hemolysis, and Full Virulence in Insects. J. Bacteriol.
182: 107-115
[Abstract]
[Full Text]