Introduction

Lice belong to the larger, monophyletic assemblage or proposed superorder of the Para-neoptera encompassing the Psocoptera (psocids or booklice, barklice and barkflies, and formerly Corrodentia), Phthiraptera (true lice), Thysanoptera (thrips), and the Hemip-tera (true bugs including, among others, leafhoppers, treehoppers, cicadas, aphids, scale insects, whiteflies, psyllids, spittlebugs, and ground pearls). Increasingly, the psocids and true lice are grouped together as Psocodea opposite the...

Ischnocera

Ischnocera is the largest suborder of lice with more than 2,700 described species . It has as sister clades the lice suborders Rhyncophthirina and Anoplura . Most species feed on birds . A small group in the family Trichophilopteridae comprises parasites of lemurs and indriids . The basalmost family of the Ischnocera is the family Trichodectidae or mammal chewing lice, whose members feed off eutherian mammals (Grimaldi and Engel, 2005) Eutherians are placental mammals as opposed to monotremes...

References

Alma, A ., Arno, C ., Arzone, A ., and Vidano C . (1988) . New biological reports on Auchenorrhyncha in vineyards . In Proc. 6th Auchenorrhyncha Meeting, pp . 509-516. Turin, Italy, September 7-11 . Alma, A ., Bosco, D., Danielli, A ., Bertaccini, A ., Vibio, M., and Arzone, A . (1997) . Identification of phytoplasma in eggs, nymphs and adults of Scaphoideus titanus Ball reared on healthy plants Insect Mol. Biol. 6 115-121 . Angelini, E , Clair, D , Borgo, M , Bertaccini, A , and Boudon-Padieu,...

Amino acid metabolisms complementary to Buchnera

Real-time quantitative RT-PCR further verified the conspicuous upregulation of genes related to amino acid metabolisms (Figure 8 . 2A) . The bacteriocyte is the cell for harboring Buchnera, whose primary role is the synthesis of essential amino acids (Sasaki and Ishi-kawa, 1995 Febvay et al , 1995 Douglas, 1998) The genome analyses of Buchnera showed that these symbionts are specialized in production of essential amino acids genes for synthesis of essential amino acids are retained, whereas...

Rickettsia as obligate and mycetomic endosymbionts

In the booklouse Liposcelis bostrychophila (Liposcelidae, Psocoptera), Rickettsia-like organisms were first observed by electron microscopy in the ovaries, oocytes, abdominal sub-epidermal tissues, esophageal epithelial cells, and subesophageal ganglion cells (Yusuf et al , 2000 Yusuf and Turner, 2004 Chapman, 2005) Yusuf and Turner performed the first molecular characterization of the intracellular bacteria (Yusuf and Turner, 2004) These bacteria have now been confirmed to be Rickettsia by...

Antimicrobial peptides to kill gut symbionts

Lytic peptides, which are a ubiquitous part of the nonspecific immune system of eukary-otes, disrupt the membranes of bacteria and protozoa by forming channels that lead to cell death (Mutwiri et al , 2000 Boman, 1995, 2003) Because lytic peptides are largely inactive against the electrically neutral, cholesterol-containing cell membranes of higher eukary-otes (Javadpour et al ., 1996 Kamysz et al ., 2003 Boman, 2003), most lytic peptides have low or no toxicity to nontarget organisms such as...

Transcriptomics of the aphid bacteriocyte Seeking the hosts role

The complete genome sequences of four lineages of Buchnera gave comprehensive information on potential functions of Buchnera in the symbiotic system (Shigenobu et al , 2000 Tamas et al ., 2002 van Ham et al ., 2003 P rez-Brocal et al ., 2006) . The genomes were 0 .420 . 65 Mb in size, which encoded 360-580 proteins (Table 8 . 1) . The gene composition corroborated the experimental data that primary role of Buchnera in the bacteriocyte symbiosis is to provide their hosts with essential amino...

Inherited symbionts in grapevinefeeding leafhoppers and planthoppers

Among symbionts that revealed a major interest in recent years are those able to spread into insect host populations by manipulating host reproduction These microorganisms are intracellular symbionts able to enter female germ line cells and to be directly transmitted to the progeny The most known models of these manipulators of host reproduction are the a-Proteobacterium Wolbachia and the Bacteroidetes Cardinium In particular for Wolbachia a vast literature has been produced in the last few...

Dedication to Paul Baumann

I still remember very clearly my first conversation with Paul Baumann . He had phoned to ask if I might be interested in collaborating on a study on the bacterial endosymbionts of aphids the year was 1990. His excitement was infectious I had read much of Paul Buchner's book as a graduate student but had never considered working on symbionts and knew almost nothing of microbiology During the earlier parts of his career, Paul had already contributed major work on topics related to marine bacteria...

Mycetomes and endosymbionts in Phthiraptera

Lice feed on the protein keratin in hair or feathers, oily secretions, and or blood . Blood is obtained by sucking lice through vessel or capillary feeding (solenophagy), whereas chewing or biting lice engage in pool feeding (telmophagy) As such, many chewing lice are considered to have a mixed diet of keratin feeding as the norm and feeding on skin and blood pools as the exception The existence and extent of blood feeding of chewing lice is in most cases not known or controversial Lice...

Diversity and sample

In addition to purely methodological issues connected to phylogenetic inference, coevolu-tionary reconstructions are burdened by another problem the reliability of any evolutionary interpretation depends on the sufficiency of the analyzed sample The current pace of new symbiont descriptions being published and sequences being deposited into databases indicates that our knowledge on diversity as a whole is still incomplete Various screenings focused on a taxonomically restricted group of insects...

Growth conditions

Once bacteria have been isolated from an insect host, they must be maintained in a culture medium that provides all of the nutrients that are necessary for growth Because symbi-onts normally live in a stable and nutrient-rich host environment, they are expected to display reduced metabolic plasticity in comparison to free-living relatives The genomic content and the level of specialization toward the host ultimately dictate the nutritional and environmental requirements of each symbiont. Given...

Mycetomes In Oriental Fruit

L ., Van Elsas, J . D., and de Bruijn, F.J . (2004) . Molecular microbial ecology manual, 2nd ed . Kluwer Academic Publishers, Dordrecht . Apidianakis, Y., Mindrinos, M . N ., Xiao, W., et al . (2005) . Profiling early infection responses Pseudomonas aeruginosa eludes host defenses by suppressing antimicrobial peptide gene expression . Proc. Nat. Acad. Sci. U.S.A. 102 2573-2578. Barneah, O., Ben-Dov, E ., Kramarsky-Winter, E ., et al . (2007) . Characterization of black band...

The significance of molecular phylogenetics for insect symbiont research

Investigation into prokaryote evolution is one of the areas of biology most deeply affected by the advent of molecular phylogenetics (Pace, 1997) . In the field of insect-bacteria symbiosis, this new approach not only generated an immense amount of knowledge, but also fundamentally changed the whole framework of this field bacterial symbionts are now mostly viewed and analyzed in terms of phylogenetic lineages. This situation contrasts with the premolecular era, when morphological and...

Medical implications of endosymbionts of human lice

Infestations of head lice among schoolchildren are increasing dramatically as resistance to the insecticides used in shampoo-based treatments becomes more common The identification of the endosymbiotic bacterium of human head and body lice might facilitate the development of antibiotic treatments as a supplement to conventional pediculosis treatments based on the neurotoxicity of insecticides to kill lice It is likely that this new, highly modified endosymbiont of lice, Riesia pediculicola,...

Evolution of obligate nonnutritional endosymbionts

Obligate nonnutritional endosymbionts come in various guises and graduations Several families of marine fish and squid employ luminous bacteria in displays that are associated with sex-specific signaling, predator avoidance, locating or attracting prey, and schooling The host provides a dedicated organ, the light organ, to host bacteria belonging to the genera Photobacterium and Vibrio (both Vibrionaceae, y-Proteobacteria) . The light organ typically accommodates and nurtures a single...

Phytoplasma vectors

Phytoplasmas belong to the class Mollicutes and are phytopathogenic agents that are non-culturable in vitro They are obliged parasites, localized in the phloem tubes and the companion cells Thanks to their small size and the lack of a cell wall they can move from one cell to the other through the pores of the sieve plates They are associated with over 1,000 diseases of wild and cultivated plants all over the World (Lee et al ., 2000) . The diseases caused by phytoplasmas, creating serious...

Effects of symbiont infection on host fitness and phenotype

In all of the four species, the adult emergence rate without symbiont capsules was drastically reduced in comparison to that with symbiont capsules . In M. punctatissima and M. Figure 5.10 Effects of symbiont elimination on adult emergence rate of the plataspid stinkbugs . (A) Megacopta punctatissima . (B) Megacopta cribraria . (C) Brachyplatys subaeneus . (D) Coptosoma parvipictum . (From Hosokawa, T., Kikuchi, Y., Nikoh, N ., Shimada, M., and Fukatsu T. 2006 . PLoS Biol. 4 e337. With...

Bacterial diversity in the gut of the Formosan subterranean termite

A prototype gene-shuttle was assembled in yeast and used in termite feeding experiments death of the protozoa in the termite gut provided proof of concept for the use of paratrans-genesis in termite control The ultimate goal for environmentally safe field applications, however, is to use novel bacteria that are exclusively found in the termite gut as shuttles and expression systems Termite-specific bacteria species would not be able to survive for a prolonged time outside the termite gut and...

Evolution of Rickettsia

The scenario of phenotypic evolution of Rickettsia as pathogens in relation to their tick, mite, and insect hosts and vectors seem to be simple The presumed old associations of spotted fever group Rickettsia with their tick and mite hosts and vectors are characterized by no adverse effects to the ticks, transovarial transmission of the Rickettsia from mother to offspring, and transstadial transmission to adults The sexual transmission of R. rickettsii might be interpreted as a transitional...

Leafhopper and planthopper vectors of phytoplasmas in grapevine

Grapevine yellows associated with phytoplasmas are among the main problems of viticulture worldwide . Currently, three types of yellows are present in Europe, and are caused by phytoplasmas belonging to two ribosomal groups (a) flavescence dor e (FD) (subgroups -C and -D) and Palatinate grapevine yellows (PGY) (subgroup -A), belonging to the elm yellows group 16SrV, and (b) bois noir (BN) belonging to the stolbur group (16SrXII-A) . The grapevines affected by different phylogenetic groups of...

Bacteria in the medfly

Until recently, the association between the Mediterranean fruit fly (medfly) and bacteria received little scrutiny Marchini et al (2002) studied the bacteria associated with the Table 11.1 Bacteria Associated with Tephritid Fruit Flies Adult gut, pupae, eggs, infested fruit Adult gut, pupae, eggs, infested fruit Adult gut, pupae, eggs, infested fruit Adult gut, pupae, eggs, infested fruit Adult esophageal bulb, gut, ovipositor Adult crop, gut, mouthparts host plant Enterobacter cloacae...

Mycetomes in Psocoptera

Psocids are microbial surface feeders Toothed laciniae enable them to scrape spores, fungal hyphae, lichens, algae, and films of yeast or bacteria from the surfaces of living and decaying plants Typical habitats are found under bark and stones, on leaf litter, in galleries of wood-boring insects, in caves, and in nests of paper wasps and bees, termites, ants, and vertebrates (Grimaldi and Engel, 2005) . With such a rich diet, primary or nutritional endo-symbionts are not expected . Obligate...

Hyalesthes obsoletus and bois noir

Bois noir phytoplasmosis was indicated since the beginning, for some infectivity features (nonepidemic), as a grapevine disease close but not identical to FD, because it is not transmissible by means of the leafhopper S. titanus Current knowledge confirms that BN is caused by a phytoplasma nonspecific for grapevine, transmitted by not strictly ampelo-phagous vector(s) Such an epidemiological situation, distinctly different from FD, reflects on the life cycle of the etiological agent of BN,...

Proof of concept of the use of paratransgenesis in the Formosan subterranean termite

The Formosan subterranean termite, Coptotermes formosanus, is one of the most economically significant invasive termite species, and therefore, an important target for developing increasingly efficient control methods, preferably without the use of pesticides Su and Scheffrahn, 1998 . In a first experiment leading to proof of concept of paratransgenesis in subterranean termites, Husseneder et al . 2005a genetically engineered an Escherichia coli laboratory strain with a plasmid that expressed...

Evolutionary consequences of Wolbachiaisopod interactions Diverse sexratio distorters in Armadillidium vulgare

In A. vulgare, chromosomal sex determination follows a female heterogamety i.e ., ZW females and ZZ males Juchault and Legrand, 1972 . Two parasitic feminizing factors are known in this species . The first one is the Wolbachia endosymbiont, which is located in all tissues of females and especially concentrated in oocytes Martin et al ., 1973 Rigaud et al , 1991 Whatever their sexual genotype, all zygotes inheriting Wolbachia will develop a female phenotype In this respect, ZZ males are changed...

Hostsymbiont cospeciation despite the midgut extracellular symbiosis

Figure 5 . 12 shows the comparison between the host phylogeny and the symbiont phylog-eny of the plataspid stinkbugs Strikingly, the phylogenetic relationship of the host insects agrees perfectly with the phylogenetic relationship of their symbiotic bacteria . On account -Poecilocoris lewisi Scutelleridae AB240574 100 I-Agonoscelis nubila Pentatomidae AB240572 -Paromius exiguus Lygaeidae AB240576 -Plautia crossota Pentatomidae AB240573 --Brachyplatys subaeneus----- Buchnera aphidicola aphid...

Characterization of Burkholderia symbiont in alydid stinkbugs

Members of the stinkbug family Alydidae, called broad-headed bugs, are distributed worldwide and include a number of pest species for leguminous and gramineous crops Schaefer and Panizzi, 2000 . In Japan, the alydid stinkbugs Riptortus pedestris Figure 7. 1 , formerly known as R. clavatus and recently renamed by Kikuhara 2005 , and Leptocorisa chinensis are notorious pests of soybean and rice, respectively Schaefer and Panizzi, 2000 Tomokuni et al., 1993 . The bean bug and the rice bug can be...

Contributors

Dipartimento di Valorizzazione e Protezione delle Risorse Agroforestali Universita degli Studi di Torino Torino, Italy Dipartimento di Patologia Animale Igiene e Sanita Pubblica Veterinaria Universita degli Studi di Milano Milano, Italy Departments of Microbiology and Entomology Hebrew University of Jerusalem Rehovot, Israel Department of Microbiology Hebrew University of Jerusalem Rehovot, Israel Laboratoire Ecologie Evolution Symbiose Universit de Poitiers Poitiers, France School of...

Intragenomic heterogeneity

In bacteria, the intragenomic heterogeneity of the 16S-23S-5S rRNA operon rRNA operon thereafter and its influence on phylogenetic reconstruction in closely related species has previously been shown in a taxonomically broad range of free-living species Luz et al , 1998 Pettersson et al ., 1998 Yap et al ., 1999 Marchandin et al ., 2003 Boucher et al ., 2004 Lin et al ., 2004 . Moreover, it was studied in detail for the Escherichia Shigella branch Cilia et al , 1996 Garcia-Martinez et al , 1996...