Cockroaches :: parasitology
J Parasitol. 2012 Jun ;98 (3):572-83 22150235
Synoptic revision of Blabericola (Apicomplexa: Eugregarinida: Blabericolidae) parasitizing blaberid cockroaches (Dictyoptera: Blaberidae), with comments on delineating gregarine species boundaries.
Department of Natural Science, Peru State College, Peru, Nebraska 68421, USA. firstname.lastname@example.org
Complete synoptic redescriptions, including complete morphometric data for all life cycle stages, species recognition characters, and differential comparisons are presented for the 4 gregarine species comprising Blabericola . Blabericola cubensis ( Peregrine, 1970 ), Blabericola haasi (Geus, 1969), Blabericola migrator ( Clopton, 1995 ), and Blabericola princisi ( Peregrine, 1970 ) are redescribed from their type hosts, i.e., the discoid cockroach Blaberus discoidalis , the lobster cockroach Nauphoeta cinerea , the Madagascar hissing cockroach Gromphadorhina portentosa , and the Bolivian cockroach Blaberus boliviensis , respectively. These gregarine species descriptions are stabilized through deposition of extensive new voucher collections. Species of Blabericola are distinguished by differences in relative metric ratios, morphology of oocysts, and by relative metric ratios of mature gamonts in association. This work is discussed as a model for morphological species descriptions in the Eugregarinorida including the 6 principles for morphological gregarine species descriptions, i.e., a centroid and population variation approach, adequate sample size, partitioning developmental variation and sexual dimorphism, recognition and minimization of fixation and physiological artifacts to eliminate false morphotypes, and comparative data sets across multiple life cycle stages.
Most cited papers:
Brigitte Boxma, Rob M de Graaf, Georg W M van der Staay, Theo A van Alen, Guenola Ricard, Toni Gabaldón, Angela H A M van Hoek, Seung Yeo Moon-van der Staay, Werner J H Koopman, Jaap J van Hellemond, Aloysius G M Tielens, Thorsten Friedrich, Marten Veenhuis, Martijn A Huynen, Johannes H P Hackstein
Hydrogenosomes are organelles that produce ATP and hydrogen, and are found in various unrelated eukaryotes, such as anaerobic flagellates, chytridiomycete fungi and ciliates. Although all of these organelles generate hydrogen, the hydrogenosomes from these organisms are structurally and metabolically quite different, just like mitochondria where large differences also exist. These differences have led to a continuing debate about the evolutionary origin of hydrogenosomes. Here we show that the hydrogenosomes of the anaerobic ciliate Nyctotherus ovalis, which thrives in the hindgut of cockroaches, have retained a rudimentary genome encoding components of a mitochondrial electron transport chain. Phylogenetic analyses reveal that those proteins cluster with their homologues from aerobic ciliates. In addition, several nucleus-encoded components of the mitochondrial proteome, such as pyruvate dehydrogenase and complex II, were identified. The N. ovalis hydrogenosome is sensitive to inhibitors of mitochondrial complex I and produces succinate as a major metabolic end product--biochemical traits typical of anaerobic mitochondria. The production of hydrogen, together with the presence of a genome encoding respiratory chain components, and biochemical features characteristic of anaerobic mitochondria, identify the N. ovalis organelle as a missing link between mitochondria and hydrogenosomes.
Toxoplasma gondii was isolated from 3.5% of 202 Mus musculus, 12.5% of 120 Rattus norvegicus, 16% of 106 sparrows (Zonotrichia capensis), and from 54% of 50 chickens from Costa Rica. The infection rate in chickens increased from 23% in those weighing less than 500 g, to 73% in those between 500 and 1,000 g, indicating a rapid rate of acquiring infectin, probably from the soil in which they constantly search for food. No isolates were made from Musca domestica, or from four genera of roaches caught in the wild. However, Toxoplasma was isolated from four of 16 lots of earthworms. Most strains of Toxoplasma isolated from Costa Rican cats produced chronic latent infections in mice. However, even when infected with virulent strains, mice died at a time when numerous bradyzoites had been formed. Also, the availability of bradyzoites in chickens 8-10 days after ingestion of oocysts was comparable to that in mice. Therefore, several infected prey species are available as intermediate hosts to cats, providing the bradyzoites essential for the shedding of large numbers of oocysts. The isolation of Toxoplasma from earthworms or the soil associated with them illustrates their possible role as transport hosts to infect chickens and other birds feeding on them. The possible role of other transport hosts could not be confirmed.
Identification and characterization of ectosymbionts of distinct lineages in Bacteroidales attached to flagellated protists in the gut of termites and a wood-feeding cockroach.
Satoko Noda, Tetsushi Inoue, Yuichi Hongoh, Miho Kawai, Christine A Nalepa, Charunee Vongkaluang, Toshiaki Kudo, Moriya Ohkuma
PRESTO, Japan Science and Technology Agency, JST, Wako, Saitama 351-0198, Japan.
Bacterial attachments to nearly the entire surface of flagellated protists in the guts of termites and the wood-feeding cockroach Cryptocercus are often observed. Based on the polymerase chain reaction-amplified 16S rRNA gene sequences, we investigated the phylogenetic relationships of the rod-shaped, attached bacteria (ectosymbionts) of several protist species from five host taxa and confirmed their identity by fluorescence in situ hybridizations. These ectosymbionts are affiliated with the order Bacteroidales but formed three distinct lineages, each of which may represent novel bacterial genera. One lineage consisted of the closely related ectosymbionts of two species of the protist genus Devescovina (Cristamonadida). The second lineage comprised three phylotypes identified from the protist Streblomastix sp.(Oxymonadida). The third lineage included ectosymbionts of the three protist genera Hoplonympha, Barbulanympha and Urinympha in the family Hoplonymphidae (Trichonymphida). The ultrastructural observations indicated that these rod-shaped ectosymbionts share morphological similarities of their cell walls and their point of attachment with the protist but differ in shape. Elongated forms of the ectosymbionts appeared in all the three lineages. The protist cells Streblomastix sp. and Hoplonympha sp. display deep furrows and vane-like structures, but these impressive structures are probably evolutionarily convergent because both the host protists and their ectosymbionts are distantly related.
Inheritance and diversification of symbiotic trichonymphid flagellates from a common ancestor of termites and the cockroach Cryptocercus.
Ecomolecular Biorecycling Science Research Team, RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198, Japan. email@example.com
Cryptocercus cockroaches and lower termites harbour obligate, diverse and unique symbiotic cellulolytic flagellates in their hindgut that are considered critical in the development of social behaviour in their hosts. However, there has been controversy concerning the origin of these symbiotic flagellates. Here, molecular sequences encoding small subunit rRNA and glyceraldehyde-3-phosphate dehydrogenase were identified in the symbiotic flagellates of the order Trichonymphida (phylum Parabasalia) in the gut of Cryptocercus punctulatus and compared phylogenetically to the corresponding species in termites. In each of the monophyletic lineages that represent family-level groups in Trichonymphida, the symbionts of Cryptocercus were robustly sister to those of termites. Together with the recent evidence for the sister-group relationship of the host insects, this first comprehensive study comparing symbiont molecular phylogeny strongly suggests that a set of symbiotic flagellates representative of extant diversity was already established in an ancestor common to Cryptocercus and termites, was vertically transmitted to their offspring, and subsequently became diversified to distinct levels, depending on both the host and the symbiont lineages.
Department of Microbiology, All India Institute of Medical Sciences, New Delhi.
A study was conducted to isolate and identify microorganisms of medical importance from cockroaches (Blattella germanica) and to ascertain their vector potential in the epidemiology of nosocomial infections. Bacteria, fungi and parasites of medical importance were isolated and identified. Important bacterial pathogens responsible for wound infections, were further studies by antibiograms. One hundred and fifty-eight out of 159 (99.4%) cockroaches collected from hospital (test) and 113 out of 120 (94.2%) cockroaches collected from residential areas (control) were carrying medically important microorganisms (P less than 0.05). significantly higher (P less than 0.001) number of test cockroaches were carrying a higher bacterial load (1 x 10(4) and 1 x 10(5] as compared to control cockroaches. Multiple drug-resistant bacterial were isolated from test cockroaches. The diversity of drug-resistant bacterial species isolated from test cockroaches suggests their involvement in the transmission of drug-resistant bacteria. Various fungi and parasitic cysts of medical importance were also isolated from the test and control cockroaches, but the carriage rates were low. The findings suggest that cockroaches, in hospitals, can act as potential vectors of medically important bacteria/parasites/fungi.
The candidate phylum 'Termite Group 1' of bacteria: phylogenetic diversity, distribution, and endosymbiont members of various gut flagellated protists.
Environmental Molecular Biology Laboratory, RIKEN, Saitama, Japan. firstname.lastname@example.org
The candidate phylum 'Termite Group 1'(TG1) of bacteria, which is abundant in termite guts but has no culturable representative, was investigated with respect to the in situ localization, distribution, and diversity. Based on the 16S rRNA gene sequence analyses and FISH in termite guts, a number of lineages of TG1 members were identified as endosymbionts of a variety of gut flagellated protists from the orders Trichonymphida, Cristamonadida, and Oxymonadida that are mostly unique to termites. However, the survey in various environments using specific PCR primers revealed that TG1 members were also present in termites, a cockroach, and the bovine rumen that typically lack these protist orders. Most of the TG1 members from gut flagellates, termites, cockroaches, and the rumen formed a monophyletic subcluster that showed a shallow branching pattern in the phylogenetic tree, suggesting their recent diversification. Although endosymbionts of the same protist genera tended to be closely related, the endosymbiont lineages were often independent of the higher level classifications of their host protist and were dispersed in the phylogenetic tree. It appears that their cospeciation is not the sole rule for the diversification of TG1 members of endosymbionts.
Department of Microbiology and Evolutionary Biology, Faculty of Science, University of Nijmegen, The Netherlands.
Aerobic and anaerobic ciliates swim towards the cathode when they are exposed to a constant DC field. Nyctotherus ovalis from the intestinal tract of cockroaches exhibits a different galvanotactic response: at low strength of the DC field the ciliates orient towards the anode whereas DC fields above 2-4 V/cm cause cathodic swimming. This reversal of the galvanotactic response is not due to backward swimming. Rather the ciliates turn around and orient to the cathode with their anterior pole. Exposure to various cations, chelators, and Ca(2+)-channel inhibitors suggests that Ca(2+)-channels similar to the "long lasting" Ca(2+)-channels of vertebrates are involved in the voltage-dependent anodic galvanotaxis. Evidence is presented that host-dependent epigenetic factors can influence the voltage-threshold for the switch from anodic to cathodic swimming.
Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA. email@example.com
The filthy breeding habits, feeding mechanisms, and indiscriminate travel between filth and food make some groups of synanthropic insects such as nonbiting flies and cockroaches efficient vectors of human enteric protozoan parasites. Twenty-one species of filth flies have been listed by regulatory agencies concerned with sanitation and public health as causative agents of gastrointestinal diseases based on synanthropy, endophily, communicative behavior, and strong attraction to filth and human food. Outbreaks and cases of food-borne diarrheal diseases in urban and rural areas are closely related to the seasonal increase in abundance of filth flies, and enforced fly control is closely related to reductions in the occurrence of such diseases. Mechanical transmission of human parasites by nonbiting flies and epidemiological involvement of other synanthropic insects in human food-borne diseases have not received adequate scientific attention.