The filamentous morphotype Eikelboom Type 1863 is not a single genetic entity

Abstract

Five isolates of a filamentous bacterial morphotype with the distinctive diagnostic microscopic features of Eikelboom Type 1863 were obtained from activated sludge sewage treatment plants in Victoria, Australia. On the basis of phenotypic evidence and 16S rDNA sequence data, these isolates proved to be polyphyletic. Two (Ben 06 and Ben 06C) are from the Chryseobacterium subgroup which is in the Cytophaga group, subdivision I of the Flexibacter–Cytophaga–Bacteroides phylum. Two (Ben 56 and Ben 59) belong to the genus Acinetobacter, and one (Ben 58) is a Moraxella sp., closest to Mor. osloensis. The significance of these findings to the reliance on microscopic features for identification of these filamentous bacteria in activated sludge is discussed.

A review of practical tools for rapid monitoring of membrane bioreactors

“…For example some filamentous organisms are able to revert to a unicellular form at some stages of their lifecycle (Ramothokang et al, 2006). Other morphological groups such as 'Eikelboom Type 1863' have been shown to comprise of several unrelated taxa (Seviour et al, 1997) (therefore a confidence and utility score 3). Although clearly basic light microscopy has its limitations, it is currently the only practical microbial ecology tool available (overall score 24/30).…”

Activated Sludge Separation Problems: Theory, Control Measures, Practical Experiences

“…However, work here and in Linda Blackall's laboratory at the University of Queensland has successfully led to the culture of many Australian filamentous bacteria Bradford et al 1996;Seviour et al 1997), and so their taxonomic positions have now been resolved for the first time. Furthermore, the availability of gene probes (Amann et al 1995) based on the 16S rRNA sequences of these filamentous bacteria now provide the means to determine unequivocally the biogeography and biodiversity of the filamentous bacteria globally.…”

Isolates of ‘Candidatus Nostocoida limicola’ Blackall et al. 2000 should be described as three novel species of the genus Tetrasphaera, as Tetrasphaera jenkinsii sp. nov., Tetrasphaera vanveenii sp. nov. and Tetrasphaera veronensis sp. nov.

“…For example, some of the Gram-positive and Gram-negative filamentous bacteria responsible for the operational disorders of bulking and foaming have now been grown in pure culture and, on the basis of 16S rRNA gene sequence data, their phylogeny has been elucidated (Kämpfer & Wagner, 2002;Martins et al, 2004). Some, like 'Microthrix parvicella' (Blackall et al, 1994;Rossetti et al, 2005) and Eikelboom type 1851 (Beer et al, 2002), are novel bacteria, while others, like type 1863 (Seviour et al, 1997), are close relatives of previously described non-filamentous bacteria. Of these filaments, 'Nostocoida limicola' is particularly interesting.…”