Publications

physical map of a plasmid from caedibacter taeniospiralis 51.	caedibacter taeniospiralis 51 carries at least two plasmids, pkap51 and pkap52. the smaller plasmid, pkap51, contains 43 kilobase pairs. the larger plasmid, pkap52, contains more than 110 kilobase pairs. relative positions of recognition sequences for seven different restriction endonucleases were determined, and a physical map of pkap51, consisting of a total of 28 restriction sites, was constructed.	1982	6290459
cloning and expression of dna sequences associated with the killer trait of paramecium tetraurelia stock 47.	we have presented direct evidence that at least one of the traits associated with killing of paramecia by kappa particles is determined by an extrachromosomal genetic element. plasmid dna was isolated from caedibacter taeniospiralis 47 (commonly known as 47 kappa), which is an obligate cytoplasmic endosymbiont of paramecium tetraurelia. fragments of pkap47 dna generated by pst i digestion were inserted into pbr328 and then introduced into escherichia coli 294 by transformation. clones carrying r ...	1983	6571998
plasmids from bacterial endosymbionts of hump-killer paramecia.	six isolates of caedibacter taeniospiralis, collected from four continents, were screened for plasmid dna. plasmid dna species containing between 41.5 and 49.5 kilobase pairs (kb) were observed in all strains. physical maps of plasmids were constructed by determining relative positions of the restriction endonuclease (bamhi, sali, xhoi, saci, psti, avai, and ecori) recognition sequences in each plasmid. the physical map of the smallest plasmid (41.5 kb), pkap30, is reflected in each of the plasm ...	1983	6306706
organization and expression of genetic determinants for synthesis and assembly of type 51 r bodies.	type 51 r bodies are produced by all bacterial endosymbionts (caedibacter taeniospiralis) of paramecium tetraurelia that confer the hump-killer trait upon their hosts. type 51 r-body synthesis by c. taeniospiralis is required for expression of the hump-killer trait. the genetic determinants for type 51 r-body synthesis by c. taeniospiralis 47 have been cloned and expressed in escherichia coli. in this communication we describe three species of polypeptides required for r-body synthesis and the o ...	1986	3759909
extrachromosomal elements of extrachromosomal elements of paramecium and their extrachromosomal elements.	expression of killer traits in paramecium is due to a complex interaction between the lower eukaryote host and two or three elements that can be viewed either as extrachromosomal elements or as endosymbionts. in all cases, the determinants of the killer trait are carried by obligate bacterial endosymbionts belonging to the genus caedibacter. however, the actual genetic determinants for expression of these traits are not an integral part of the symbiont genome. they are located on extrachromosoma ...	1986	3032139
transposonlike elements in caedibacter taeniospiralis.	we report that the 1.5- and 7.5-kilobase-pair (kbp) transposonlike sequences present in the r-body-coding plasmids of caedibacter taeniospiralis share homology. the r-body-coding plasmids of two new strains of c. taeniospiralis, derived from strains 169 and a30, carry the 7.5- and 1.5-kbp elements, respectively, inserted at new positions. sequences homologous to the 7.5-kbp sequence from c. taeniospiralis 47 were detected in the chromosomes of three other strains of c. taeniospiralis.	1986	3007438
a mutation in the r body-coding sequence destroys expression of the killer trait in p. tetraurelia.	this report describes a mutant strain of caedibacter taeniospiralis 169 that does not produce refractile (r) bodies or kill sensitive paramecia, but still renders its host resistant to killing by wild-type strains of caedibacter taeniospiralis. the mutation is due to insertion of a 7.5-kilobase, transposon-like element into the r body-coding region of the plasmid pkap169. the results provide strong evidence that r body synthesis is required for expression of the killer trait.	1986	3008334
characterization of caedibacter endonucleobionts from the macronucleus of paramecium caudatum and the identification of a mutant with blocked r-body synthesis.	cytology, dna and host-symbiont relationships of x-like endosymbionts from paramecium caudatum are described. the symbionts (caedibacter caryophila, sp. nov.) live in the macronuclei of their hosts. they confer the killer trait upon their hosts and appear well adapted to their endonucleobiotic way of life. r bodies (proteinaceous ribbons associated with killing) are produced, but differ significantly from any of the four r-body classes previously described. c. caryophila and their r bodies were ...	1988	3335230
r-body-producing bacteria.	until 10 years ago, r bodies were known only as diagnostic features by which endosymbionts of paramecia were identified as kappa particles. they were thought to be limited to the cytoplasm of two species in the paramecium aurelia species complex. now, r bodies have been found in free-living bacteria and other paramecium species. the organisms now known to form r bodies include the cytoplasmic kappa endosymbionts of p. biaurelia and p. tetraurelia, the macronuclear kappa endosymbionts of p. cauda ...	1989	2651865
occurrence of fragmented 16s rrna in an obligate bacterial endosymbiont of paramecium caudatum.	the phylogenetic position of caedibacter caryophila, a so far noncultured killer symbiont of paramecium caudatum, was elucidated by comparative sequence analysis of in vitro amplified 16s rrna genes (rdna). c. caryophila is a member of the alpha subclass of the proteobacteria phylum. within this subclass c. caryophila is moderately related to holospora obtusa, which is another obligate endosymbiont of paramecium caudatum, and to rickettsia. a 16s rrna targeted specific hybridization probe was de ...	1993	8234331
characterization of genetic determinants for r body synthesis and assembly in caedibacter taeniospiralis 47 and 116.	caedibacter taeniospiralis, an obligate bacterial endosymbiont of paramecium tetraurelia, confers a killing trait upon its host paramecium. type 51 r bodies (refractile inclusion bodies) are synthesized by these endosymbionts and are required for expression of the killing trait. the nucleotide sequence of the genetic determinants for type 51 r body synthesis and assembly was determined for c. taeniospiralis 47 and 116. three independently transcribed genes (reba, rebb, and rebc) were characteriz ...	1994	8206833
molecular phylogeny and in situ detection of the etiologic agent of necrotizing hepatopancreatitis in shrimp.	necrotizing hepatopancreatitis (nhp) is a severe disease of farm-raised penaeus vannamei that has been associated with mortality losses ranging from 20 to 95%. nhp was first recognized in texas in 1985 (s. k. johnson, p. 16, in handbook of shrimp diseases, 1989) and is an economically important disease that has limited the ability to culture shrimp in texas. the putative cause of nhp is a gram-negative, pleomorphic, intracellular, rickettsia-like bacterium that remains uncultured in part because ...	1996	8795235
novel bacterial endosymbionts of acanthamoeba spp. related to the paramecium caudatum symbiont caedibacter caryophilus.	acanthamoebae are increasingly being recognized as hosts for obligate bacterial endosymbionts, most of which are presently uncharacterized. in this study, the phylogeny of three gram-negative, rod-shaped endosymbionts and their acanthamoeba host cells was analysed by the rrna approach. comparative analyses of 16s rdna sequences retrieved from amoebic cell lysates revealed that the endosymbionts of acanthamoeba polyphaga hn-3, acanthamoeba sp. uwc9 and acanthamoeba sp. uwe39 are related to the pa ...	1999	11207753
the toxic symbiont caedibacter caryophila in the cytoplasm of paramecium novaurelia.	endosymbiotic bacteria were observed to inhabit the cytoplasm of the freshwater ciliate paramecium novaurelia. transmission electron microscopy and toxicity tests with sensitive paramecia showed that the endosymbionts belong to the genus caedibacter. the bacteria conferred a killer trait to their host paramecia. the production of a proteinaceous inclusion body ("r-body") in the bacterial cell makes them toxic to other paramecia after they become enclosed in food vacuoles. r-bodies of caedibacter ...	2000	12035091
'candidatus odyssella thessalonicensis' gen. nov., sp. nov., an obligate intracellular parasite of acanthamoeba species.	an intracellular bacterium, strain l13, was observed infecting an environmental isolate of an acanthamoeba species. the bacterium could not be recovered on axenic medium but was recovered and cultivated in vitro using cultures of acanthamoeba polyphaga. the 16s rrna gene sequence of l13 was found to be new, sharing less than 84% similarity with other sequences in the genbank/embl database. l13 was found to be a member of the alpha-proteobacteria, sharing an evolutionary line of descent with a gr ...	2000	10826788
the genus caedibacter comprises endosymbionts of paramecium spp. related to the rickettsiales (alphaproteobacteria) and to francisella tularensis (gammaproteobacteria).	obligate bacterial endosymbionts of paramecia able to form refractile inclusion bodies (r bodies), thereby conferring a killer trait upon their ciliate hosts, have traditionally been grouped into the genus caedibacter: of the six species described to date, only the paramecium caudatum symbiont caedibacter caryophilus has been phylogenetically characterized by its 16s rrna gene sequence, and it was found to be a member of the alphaproteobacteria related to the rickettsiales: in this study, the ca ...	2002	12450827
competitive advantages of caedibacter-infected paramecia.	intracellular bacteria of the genus caedibacter limit the reproduction of their host, the freshwater ciliate paramecium. reproduction rates of infected strains of paramecia were significantly lower than those of genetically identical strains that had lost their parasites after treatment with an antibiotic. interference competition occurs when infected paramecia release a toxic form of the parasitic bacterium that kills uninfected paramecia. in mixed cultures of infected and uninfected strains of ...	2002	12022275
phylogenetic relationships of non-mitochondrial nucleotide transport proteins in bacteria and eukaryotes.	current knowledge about the nucleotide metabolism of intracellular bacteria is very limited. here we report on the identification of nucleotide transport proteins (ntt) of two obligate endoparasites, caedibacter caryophila and holospora obtusa, both alpha-proteobacteria, which reside in the vegetative macronucleus of paramecium caudatum. for comparative studies, we also identified the first nucleotide transporter in chloroplasts of a red alga, i.e. galdieria sulphuraria, and further homologs in ...	2003	12657464
the nucleotide transporter of caedibacter caryophilus exhibits an extended substrate spectrum compared to the analogous atp/adp translocase of rickettsia prowazekii.	the two obligate intracellular alphaproteobacteria rickettsia prowazekii and caedibacter caryophilus, a human pathogen and a paramecium endosymbiont, respectively, possess transport systems to facilitate atp uptake from the host cell cytosol. these transport proteins, which have 65% identity at the amino acid level, were heterologously expressed in escherichia coli, and their properties were compared. the results presented here demonstrate that the caedibacter transporter had a broader substrate ...	2004	15126491
bacterial endocytobionts of ciliophora and their interactions with the host cell.	ciliates may be hosts for numerous bacteria, which can occupy almost all cellular compartments of the protists. about 200 ciliate species are recorded as hosts of different intracellular bacteria, being a small part of the diversity for such types of endocytobiosis in nature. in the paramecium genus alone close to 60 types of bacteria adapted for intracellular life are known. in this review extensive material concerning the variety of endocytobionts, their categories, and their interaction with ...	2004	15261739
sequence, transcription activity, and evolutionary origin of the r-body coding plasmid pkap298 from the intracellular parasitic bacterium caedibacter taeniospiralis.	we isolated the intracellular parasitic bacterium caedibacter taeniospiralis from cultures of the freshwater ciliate paramecium tetraurelia strain 298. plasmid pkap298 as well as the total rna were isolated from the bacteria. pkap298 was totally sequenced (49.1 kb; ncbi accession number ay422720). from southern blots of pkap-fragments and digoxigenin-labeled cdna of the caedibacter-rna, we generated transcription maps of pkap298. the observed transcription activity indicated functions of the pla ...	2005	15785846
towards an understanding of the killer trait: caedibacter endocytobionts in paramecium.		2006	16623389
molecular characterization of the obligate endosymbiont "caedibacter macronucleorum"fokin and görtz, 1993 and of its host paramecium duboscqui strain ku4-8.	bacterial endosymbionts of protozoa were often described as new species by protozoologists mainly on the basis of few morphological characters and partly by host specificity. many of these species have never been validated by prokaryotic microbiologists whose taxonomic rules are quite different from those of protozoologists, who use the zoological code of nomenclature. "caedibacter macronucleorum"fokin and görtz 1993, an endosymbiont of paramecium duboscqui, belongs to this category. here we pro ...	2006	17123414
molecular characterization of bacterial endosymbionts of acanthamoeba isolates from infected corneas of korean patients.	the endosymbionts of 4 strains of acanthamoeba (ka/e9, ka/e21, ka/e22, and ka/e23) isolated from the infected corneas of korean patients were characterized via orcein stain, transmission electron microscopic examination, and 16s rdna sequence analysis. double membrane-bound, rod-shaped endosymbionts were distributed randomly throughout both the trophozoites and cysts of each of acanthamoeba isolates. the endosymbionts of ka/e9, ka/e22, and ka/e23 were surrounded by electron-translucent areas. no ...	2007	17374972
fangia hongkongensis gen. nov., sp. nov., a novel gammaproteobacterium of the order thiotrichales isolated from coastal seawater of hong kong.	a gram-negative, coccobacillus-shaped, aerobic bacterium, designated strain ust040201-002t, was isolated in february 2004 from seawater at the outlet of a sandfilter in port shelter, hong kong sar, china. this strain possessed ubiquinone-8; its 16s rrna gene sequence shared only 91% similarity with the sequence from caedibacter taeniospiralis and 89-90% similarity with sequences from francisella tularensis, francisella novicida, francisella philomiragia and wolbachia persica. 16s rrna gene seque ...	2007	17978237
phrr-like gene prar of azorhizobium caulinodans ors571 is essential for symbiosis with sesbania rostrata and is involved in expression of reb genes.	this study focuses on the function of the gene prar that encodes a putative transcription factor in azorhizobium caulinodans ors571, a microsymbiont of sesbania rostrata. the prar gene is a homolog of the phrr gene of sinorhizobium medicae wsm419, and the prar and phrr homologs are distributed throughout the class alphaproteobacteria. the growth and nitrogen fixation activity of an a. caulinodans prar deletion mutant in the free-living state were not significantly different from those of the wil ...	2010	20382809