Alcaligenes aquatilis sp. nov., a novel bacterium from sediments of the Weser Estuary, Germany, and a salt marsh on Shem Creek in Charleston Harbor, USA.

Four nitrite-dissimilating strains, isolated from Weser Estuary sediments, were investigated using a polyphasic taxonomic approach. Phylogenetic analysis based on 16S rRNA gene sequences indicated that these strains belong to the 'Betaproteobacteria' and are related to the genus Alcaligenes. The highest level of sequence similarity (100 %) was found with strain M3A (=ATCC 700596), a dimethyl sulfide-producing marine isolate that was included in this study. DNA-DNA hybridizations between the five strains and related Alcaligenes faecalis strains confirmed that the former belong to a single and novel species within the genus Alcaligenes. The isolates are Gram-negative, motile, rod-shaped cells with a DNA G+C content of about 56 mol%. The whole-cell fatty acid profiles of the isolates were very similar and included C(16 : 0), C(17 : 0) cyclo, C(18 : 1)omega7c, summed feature 2 (comprising any combination of C(12 : 0) aldehyde, an unknown fatty acid of equivalent chain length 10.928, C(16 : 1) iso I and C(14 : 0) 3-OH) and summed feature 3 (C(15 : 0) iso 2-OH and/or C(16 : 1)omega7c) as the major fatty acid components. On the basis of their phylogenetic, genomic and phenotypic properties, the five novel strains can be assigned to the genus Alcaligenes as a novel species, for which the name Alcaligenes aquatilis sp. nov. is proposed. The type strain is LMG 22996T (=CCUG 50924T).

A novel strategy for the isolation and identification of environmental Burkholderia cepacia complex bacteria.

The purpose of this study was to develop a novel strategy for the isolation and identification of Burkholderia cepacia complex bacteria from the home environment of cystic fibrosis (CF) patients. Water and soil samples were enriched in a broth containing 0.1% l-arabinose, 0.1% l-threonine, and a mixture of selective agents including 1 microgml(-1) C-390, 600U ml(-1) polymyxin B sulfate, 10 microgml(-1) gentamycin, 2 microgml(-1) vancomycin and 10 microgml(-1) cycloheximide. On selective media (consisting of the same components as above plus 1.8% agar), several dilutions of the enrichment broth were inoculated and incubated for 5 days at 28 degrees C. Isolates with different randomly amplified polymorphic DNA patterns were inoculated in Stewart's medium. Putative B. cepacia complex bacteria were confirmed by means of recA PCR and further identified by HaeIII-recA restriction fragment length polymorphism analysis. Our results suggest that these organisms may be more widespread in the home environment than previously assumed and that plant associated soil and pond water may be reservoirs of B. cepacia complex infection in CF patients.

Advenella incenata gen. nov., sp. nov., a novel member of the Alcaligenaceae, isolated from various clinical samples.

A polyphasic taxonomic study of 14 isolates recovered from various human and veterinary clinical samples was performed. Phenotypically these isolates shared several characteristics with members of the Alcaligenaceae and related genera. Random amplified polymorphic DNA fingerprinting and whole-cell protein analysis suggested the presence of multiple genomic groups, which was confirmed by DNA-DNA hybridization experiments. 16S rRNA gene sequence analysis indicated that these isolates were related to the genera Pelistega, Taylorella, Oligella, Pigmentiphaga, Alcaligenes, Kerstersia, Achromobacter and Bordetella and belonged to the family Alcaligenaceae. Based on the results of the present study the organisms were classified in a novel genus, Advenella gen. nov. This genus comprises one named species, Advenella incenata sp. nov. (type strain LMG 22250T=CCUG 45225T) and five currently unnamed genomic species. The DNA G+C content of members of the novel genus Advenella is between 54.0 and 57.7 mol%.