| tissue localization of the endosymbiotic bacterium "candidatus blochmannia floridanus" in adults and larvae of the carpenter ant camponotus floridanus. | the distribution of endosymbiotic bacteria in different tissues of queens, males, and workers of the carpenter ant camponotus floridanus was investigated by light and electron microscopy and by in situ hybridization. a large number of bacteria could be detected in bacteriocytes within the midguts of workers, young virgin queens, and males. large amounts of bacteria were also found in the oocytes of workers and queens. in contrast, bacteria were not present in oocyte-associated cells or in the sp ... | 2002 | 12200264 |
| the genome sequence of blochmannia floridanus: comparative analysis of reduced genomes. | bacterial symbioses are widespread among insects, probably being one of the key factors of their evolutionary success. we present the complete genome sequence of blochmannia floridanus, the primary endosymbiont of carpenter ants. although these ants feed on a complex diet, this symbiosis very likely has a nutritional basis: blochmannia is able to supply nitrogen and sulfur compounds to the host while it takes advantage of the host metabolic machinery. remarkably, these bacteria lack all known ge ... | 2003 | 12886019 |
| evolutionary forces in shaping the codon and amino acid usages in blochmannia floridanus. | endosymbiotic relationship has great effect on ecological system. codon and amino acid usages bias of endosymbiotic bacteria blochmannia floridanus (whose host is an ant camponotus floridanus) was investigated using experimentally known genes of this organism. correspondence analysis on rscu values show that there exists only one single explanatory major axis that is linked to the strand specific mutational biases. majority of the genes have a tendency to concentrate on the leading strand, which ... | 2004 | 15214801 |
| genome rearrangement distances and gene order phylogeny in gamma-proteobacteria. | genome rearrangements have been studied in 30 gamma-proteobacterial complete genomes by comparing the order of a reduced set of genes on the chromosome. this set included those genes fulfilling several characteristics, the main ones being that an ortholog was present in every genome and that none of them had been acquired by horizontal gene transfer. genome rearrangement distances were estimated based on either the number of breakpoints or the minimal number of inversions separating two genomes. ... | 2005 | 15772379 |
| analysis of and function predictions for previously conserved hypothetical or putative proteins in blochmannia floridanus. | there is an increasing interest to better understand endosymbiont capabilities in insects both from an ecological point of view and for pest control. blochmannia floridanus provides important nutrients for its host, the ant camponotus, while the bacterium in return is provided with a niche to proliferate. blochmannia floridanus proteins and metabolites are difficult to study due to its endosymbiontic life style; however, its complete genome sequence became recently available. | 2006 | 16401340 |
| tempo and mode of early gene loss in endosymbiotic bacteria from insects. | understanding evolutionary processes that drive genome reduction requires determining the tempo (rate) and the mode (size and types of deletions) of gene losses. in this study, we analysed five endosymbiotic genome sequences of the gamma-proteobacteria (three different buchnera aphidicola strains, wigglesworthia glossinidia, blochmannia floridanus) to test if gene loss could be driven by the selective importance of genes. we used a parsimony method to reconstruct a minimal ancestral genome of in ... | 2006 | 16848891 |
| relevance of the endosymbiosis of blochmannia floridanus and carpenter ants at different stages of the life cycle of the host. | expression of several genes possibly involved in the symbiotic relationship between the obligate intracellular endosymbiont blochmannia floridanus and its ant host camponotus floridanus was investigated at different developmental stages of the host by real-time quantitative pcr. these included a set of genes related to nitrogen metabolism (urec, uref, glna, and speb) as well as genes involved in the synthesis of the aromatic amino acid tyrosine (tyra, aspc, and hisc). the overall transcriptional ... | 2006 | 16957225 |
| identification of two inner-membrane proteins required for the transport of lipopolysaccharide to the outer membrane of escherichia coli. | the outer membrane (om) of most gram-negative bacteria contains lipopolysaccharide (lps) in the outer leaflet. lps, or endotoxin, is a molecule of important biological activities. in the host, lps elicits a potent immune response, while in the bacterium, it plays a crucial role by establishing a barrier to limit entry of hydrophobic molecules. before lps is assembled at the om, it must be synthesized at the inner membrane (im) and transported across the aqueous periplasmic compartment. much is k ... | 2008 | 18375759 |
| promoter characterization in the at-rich genome of the obligate endosymbiont "candidatus blochmannia floridanus". | the characterization of transcriptional start sites of 14 genes encoded by the extremely at-rich genome of "candidatus blochmannia floridanus" revealed a high degree of conservation with the rpod promoter consensus sequence of the free-living relative escherichia coli. moreover, in agreement with the presence of the alternative heat shock sigma factor rpoh in "ca. blochmannia," typical rpoh-dependent promoters were identified. however, no heat shock response resembling that of e. coli could be d ... | 2009 | 19329646 |
| patterns and rates of nucleotide substitution, insertion and deletion in the endosymbiont of ants blochmannia floridanus. | genome reduction is a general process that has been studied in numerous symbiotic bacteria associated with insects. we investigated the last stages of genome degradation in blochmannia floridanus, a mutualistic bacterial endosymbiont of the ant camponotus floridanus. we determined the tempo (rates of insertion and deletion) and mode (size and number of insertion-deletion events) of the process in the last 200,000 years by analysing a total of 16 intergenic regions in several strains of this endo ... | 2008 | 19378410 |
| systematic relationships and cospeciation of bacterial endosymbionts and their carpenter ant host species: proposal of the new taxon candidatus blochmannia gen. nov. | the systematic relationships of intracellular bacteria of 13 camponotus species (carpenter ants) from america and europe were compared to those of their hosts. phylogenetic trees of the bacteria and the ants were based on 16s rdna (rrs) gene sequences and mitochondrial cytochrome oxidase subunit i (coi) gene sequences, respectively. the bacterial endosymbionts of camponotus spp. form a distinct lineage in the y-subclass of the proteobacteria. the taxa most closely related to these bacteria are e ... | 2000 | 11034499 |
| immune response of the ant camponotus floridanus against pathogens and its obligate mutualistic endosymbiont. | numerous insect species harbor mutualistic endosymbionts that play a role in nutrient cycling or confer other fitness benefits to their hosts. insect hosts face the problem of having to maintain such mutualistic bacteria while staging an immune response towards pathogens upon infection. in addition, hosts may regulate the number of endosymbionts present in their tissues via the innate immune system. camponotus floridanus ants harbor the obligate endosymbiont blochmannia floridanus in specialized ... | 2011 | 21440063 |
| bacteriocyte dynamics during development of a holometabolous insect, the carpenter ant camponotus floridanus. | the carpenter ant camponotus floridanus harbors obligate intracellular mutualistic bacteria (blochmannia floridanus) in specialized cells, the bacteriocytes, intercalated in their midgut tissue. the diffuse distribution of bacteriocytes over the midgut tissue is in contrast to many other insects carrying endosymbionts in specialized tissues which are often connected to the midgut but form a distinct organ, the bacteriome. c. floridanus is a holometabolous insect which undergoes a complete metamo ... | 2010 | 21122115 |
| transcriptional profiling of the endosymbiont blochmannia floridanus during different developmental stages of its holometabolous ant host. | the transcriptome of blochmannia floridanus, the endosymbiont of the carpenter ant camponotus floridanus, is presented during various developmental stages of its holometabolous host by use of a whole-genome dna macroarray. the detected transcription patterns indicate the presence of local transcription units as well as global regulatory mechanisms. yet, the overall regulation scale is very modest, rarely exceeding a factor of three. a large number of genes show differential expression in differe ... | 2009 | 19040455 |
| nutritional upgrading for omnivorous carpenter ants by the endosymbiont blochmannia. | carpenter ants (genus camponotus) are considered to be omnivores. nonetheless, the genome sequence of blochmannia floridanus, the obligate intracellular endosymbiont of camponotus floridanus, suggests a function in nutritional upgrading of host resources by the bacterium. thus, the strongly reduced genome of the endosymbiont retains genes for all subunits of a functional urease, as well as those for biosynthetic pathways for all but one (arginine) of the amino acids essential to the host. | 2007 | 17971224 |
| from phylogenetics to phylogenomics: the evolutionary relationships of insect endosymbiotic gamma-proteobacteria as a test case. | the increasing availability of complete genome sequences and the development of new, faster methods for phylogenetic reconstruction allow the exploration of the set of evolutionary trees for each gene in the genome of any species. this has led to the development of new phylogenomic methods. here, we have compared different phylogenetic and phylogenomic methods in the analysis of the monophyletic origin of insect endosymbionts from the gamma-proteobacteria, a hotly debated issue with several rece ... | 2007 | 17366133 |
| genomic comparisons among gamma-proteobacteria. | predicted highly expressed (phx) genes are compared for 16 gamma-proteobacteria and their similarities and differences are interpreted with respect to known or predicted physiological characteristics of the organisms. predicted highly expressed genes often reflect the organism's predominant lifestyle, habitat, nutrition sources and metabolic propensities. this technique allows to predict principal metabolic activities of the microorganisms operating in their natural habitats. among our findings ... | 2006 | 16423015 |
| genome sequence of blochmannia pennsylvanicus indicates parallel evolutionary trends among bacterial mutualists of insects. | the distinct lifestyle of obligately intracellular bacteria can alter fundamental forces that drive and constrain genome change. in this study, sequencing the 792-kb genome of blochmannia pennsylvanicus, an obligate endosymbiont of camponotus pennsylvanicus, enabled us to trace evolutionary changes that occurred in the context of a bacterial-ant association. comparison to the genome of blochmannia floridanus reveals differential loss of genes involved in cofactor biosynthesis, the composition an ... | 2005 | 16077009 |
| replication of the endosymbiotic bacterium blochmannia floridanus is correlated with the developmental and reproductive stages of its ant host. | the dynamics of replication of the intracellular endosymbiotic bacterium blochmannia floridanus was determined during the larval development of its host ant camponotus floridanus by real-time quantitative pcr. the bacteria were found to proliferate during pupation and immediately after the eclosion of the imagines (adult ants). in older workers the number of bacteria present in the midgut bacteriocytes decreased significantly. in contrast, the bacterial population in the ovaries was dependent on ... | 2004 | 15240288 |