Query: NC_009792:2688747 Citrobacter koseri ATCC BAA-895, complete genome
Lineage: Citrobacter koseri; Citrobacter; Enterobacteriaceae; Enterobacteriales; Proteobacteria; Bacteria
General Information: Citrobacter koseri ATCC BAA-895 is a clinical isolate from a human infant. Causative agent of neonatal meningitis. Citrobacter koseri, previously known as Citrobacter diversus, Levinea diversus or Levinea malonatica resides in a wide range of environments, including soil, water and food products. It is an occasional inhabitant of human and animal intestines, but is mainly characterized as being a causative agent of neonatal meningitis with an extreme high rate of multiple brain abscess initiations and a concomitant high moratility rate. The bacteria are used in neonatal rat models to study the mechanism of blood-brain barrier penetration, host immune response evasion and its resistance to phagocytotic killing.
Subject: NC_005126:3485330 Photorhabdus luminescens subsp. laumondii TTO1, complete genome
Lineage: Photorhabdus luminescens; Photorhabdus; Enterobacteriaceae; Enterobacteriales; Proteobacteria; Bacteria
General Information: This strain was isolated on Trinidad and Tobago. It is a symbiont of the nematode Heterorhabditis bacteriophora. Bioluminescent bacterium. This organism is unusual in that it is symbiotic within one insect, and pathogenic in another, the only organism that is known to exhibit this dual phenotype. Enzymes are then released by the bacteria that result in rapid degradation of the insect body, allowing both bacteria and nematode to feed and reproduce. During this period Photorhabdus luminescens releases bacteriocidal products, including antibiotics and bacteriocins, that prevent infection of the larva by competitive microbes. The result is promotion of Photorhabdus luminescens-nematode interactions that result in continuation of the symbiotic relationship. In order to engage in a symbiotic relationship with the nematode and a pathogenic one with the insect larva, the bacterium encodes specific factors that encourage both. These include a large number of genes that code for secreted toxins and enzymes, as well as genes that encode products for the production of antibiotics and bacteriocins. Secretion of these products occurs by an array of systems including type I, type II, and type III secretion systems. The type III system is closely related to the Yersinia plasmid-encoded type III system. Genes that promote symbiotic relationships are also encoded on genomic islands on the chromosome including some that affect nematode development. Virulence genes appear to be active during exponential growth. Symbiotic genes appear to function during stationary phase (post-exponential) growth. The switch from one state to another is controlled. Photorhabdus luminescens is capable of giving off light, a complex process that requires the products of the lux operon.