TY - JOUR

T1 - Novel oligonucleotide probes for in situ detection of pederin-producing endosymbionts of Paederus riparius rove beetles (Coleoptera

T2 - Staphylinidae)

AU - Kador, Matthias

AU - Horn, Marcus A.

AU - Dettner, Konrad

N1 - Copyright: Copyright 2011 Elsevier B.V., All rights reserved.

PY - 2011/6

Y1 - 2011/6

N2 - Bacterial endosymbionts from female Paederus rove beetles are hitherto uncultured, phylogenetically related to Pseudomonas sp., and produce the polyketide pederin, which exhibits strong cytotoxic effects and antitumoral activities. The location of such endosymbionts inside beetles and on beetles' eggs is hypothesized based on indirect evidence rather than elucidated. Thus, an endosymbiont-specific and a competitor oligonucleotide probe (Cy3-labelled PAE444 and unlabelled cPAE444, respectively) were designed and utilized for FISH with semi-thin sections of Paederus riparius eggs. Cy3-PAE444-positive cells were densely packed and covered the whole eggshell. Hundred percent of EUB338-Mix-positive total bacterial cells were PAE444 positive, indicating a biofilm dominated by Paederus endosymbionts. Analysis of different egg deposition stadiums by electron microscopy and pks (polyketide synthase gene, a structural gene associated with pederin biosynthesis)-PCR supported results obtained by FISH and revealed that the endosymbiont-containing layer is applied to the eggshell inside the efferent duct. These findings suggest that P. riparius endosymbionts are located inside unknown structures of the female genitalia, which allow for a well-regulated release of endosymbionts during oviposition. The novel oligonucleotide probes developed in this study will facilitate (1) the identification of symbiont-containing structures within genitalia of their beetle hosts and (2) directed cultivation approaches in the future.

AB - Bacterial endosymbionts from female Paederus rove beetles are hitherto uncultured, phylogenetically related to Pseudomonas sp., and produce the polyketide pederin, which exhibits strong cytotoxic effects and antitumoral activities. The location of such endosymbionts inside beetles and on beetles' eggs is hypothesized based on indirect evidence rather than elucidated. Thus, an endosymbiont-specific and a competitor oligonucleotide probe (Cy3-labelled PAE444 and unlabelled cPAE444, respectively) were designed and utilized for FISH with semi-thin sections of Paederus riparius eggs. Cy3-PAE444-positive cells were densely packed and covered the whole eggshell. Hundred percent of EUB338-Mix-positive total bacterial cells were PAE444 positive, indicating a biofilm dominated by Paederus endosymbionts. Analysis of different egg deposition stadiums by electron microscopy and pks (polyketide synthase gene, a structural gene associated with pederin biosynthesis)-PCR supported results obtained by FISH and revealed that the endosymbiont-containing layer is applied to the eggshell inside the efferent duct. These findings suggest that P. riparius endosymbionts are located inside unknown structures of the female genitalia, which allow for a well-regulated release of endosymbionts during oviposition. The novel oligonucleotide probes developed in this study will facilitate (1) the identification of symbiont-containing structures within genitalia of their beetle hosts and (2) directed cultivation approaches in the future.

KW - Bacterial endosymbiont

KW - FISH

KW - Pederin

KW - Polyketide

KW - Pseudomonas

KW - Rove beetle

UR - http://www.scopus.com/inward/record.url?scp=79954986201&partnerID=8YFLogxK

U2 - 10.1111/j.1574-6968.2011.02270.x

DO - 10.1111/j.1574-6968.2011.02270.x

M3 - Letter

C2 - 21426381

AN - SCOPUS:79954986201

VL - 319

SP - 73

EP - 81

JO - FEMS microbiology letters

JF - FEMS microbiology letters

SN - 0378-1097

IS - 1

ER -