The cellular fatty acid content of 22 cyanobacterial strains belonging to the genera Anabaena, Aphanizomenon, Calothrix, Cylindrospermum, Nostoc, Microcystis and Planktothrix were analysed. The identities of the major peaks were confirmed by MS. Correspondence analysis of the data revealed three distinct groups formed by the Microcystis strains, the Nostoc/Planktothrix strains and the Anabaena/Aphanizomenon/Cylindrospermum strains. The Calothrix strain did not cluster with the other heterocystous cyanobacteria, supporting its morphological classification separate from the Nostocaceae family. The presence of large amounts of the fatty acids 18:30omega6,9,12c and 18:0 iso distinguished the Microcystis strains from the other cyanobacteria studied. The high content of 16:1omega7c grouped the Nostoc strains with the Planktothrix strains. A free-living strain of Nostoc contained 16:1omegao5c and 16: 1omega7c (about 1: 1), separating it from the symbiotic Nostoc strain and the Planktothrix strains. the strains of Anabaena, Aphanizomenon and Cylindrospermum grouped tightly and were characterized by the presence of 16:1omega9c and 16:0 anteiso fatty acids. Correspondence analysis of Anabaena, Aphanizomenon and Cylindrospermum showed that all hepatotoxic Anabaena strains grouped together, whereas the non-toxic and neurotoxic Anabaena strains grouped with the non-toxic Aphanizomenon strains.

Sphingomonas species were commonly isolated from biofilms in drinking water distribution systems in Finland (three water meters) and Sweden (five water taps in different buildings). The Sphingomonas isolates (n = 38) were characterized by chemotaxonomic, physiological and phylogenetic methods. Fifteen isolates were designated to species Sphingomonas aromaticivorans, seven isolates to S. subterranea, two isolates to S. xenophaga and one isolate to S. stygia. Thirteen isolates represented one or more new species of Sphingomonas. Thirty‐three isolates out of 38 grew at 5 °C on trypticase soy broth agar (TSBA) and may therefore proliferate in the Nordic drinking water pipeline where the temperature typically ranges from 2 to 12 °C. Thirty‐three isolates out of 38 grew at 37 °C on TSBA and 15 isolates also grew on blood agar at 37 °C. Considering the potentially pathogenic features of sphingomonas, their presence in drinking water distribution systems may not be desirable.

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Rubellimicrobium thermophilum gen. nov., sp. nov., a red-pigmented, moderately thermophilic bacterium isolated from coloured slime deposits in paper machines Six red-pigmented strains of the Alphaproteobacteria with optimal growth between 45 and 54 6C were previously isolated from coloured biofilms in two fine-paper machines and one pulp dryer. The strains were found to be resistant to 15 p.p.m. 2,2-dibromo-3-nitrilopropionamide, a common industrial biocide. 16S RNA gene sequence similarity of the isolates was 99?7-100 %. Ribotyping using the restriction enzymes PvuII and EcoRI showed that four of the isolates (C-lvk-R2A-1, C-lvk-R2A-2 T , C-R2A-52d and C-R2A-5d) belong to a single species. 16S rRNA gene-based phylogenetic analysis revealed that, together with Rhodobacter blasticus ATCC 33485 T , the isolates form a deep line of descent (94?7-94?9 % sequence similarity) within the family Rhodobacteraceae loosely affiliated with the Rhodobacter/Paracoccus clade. The isolates were strictly aerobic and oxidase-positive (catalase was weakly positive) and utilized a wide range of substrates including pentoses, hexoses, oligosaccharides and sugar alcohols. The predominant constituents in their cellular fatty acid profiles were C 19 : 0 cyclo v8c (39-44 %), C 18 : 0 (21-24 %) and C 16 : 0 (21-23 %). Fatty acids present in smaller amounts included C 18 : 1 v7c, C 10 : 0 3-OH, C 18 : 1 v7c 11-methyl, C 20 : 2 v6,9c and C 17 : 0 cyclo, amongst others. Polar lipids included diphosphatidylglycerol, phosphatidylcholine and an unidentified aminolipid, but not phosphatidylethanolamine. Carotenoid pigments were synthesized but bacteriochlorophyll a was not. The polyamine patterns consisted of the major compounds putrescine, spermidine and sym-homospermidine. The major respiratory lipoquinone was ubiquinone Q-10. The DNA G+C content was 69?4-70?2 mol%. On the basis of the phylogenetic and phenotypic evidence, the biofilm isolates were classified in a new genus, Rubellimicrobium gen. nov.; four of the isolates are assigned to the type species, Rubellimicrobium thermophilum gen. nov., sp. nov. Strain C-lvk-R2A-2 T (=CCUG 51817 T =DSM 16684 T =HAMBI 2421 T ) is the type strain of Rubellimicrobium thermophilum.Coloured microbial slime deposits (biofilms) in the wet end of paper machines are deleterious, particularly for white end products. Bacterial slime deposits on machine surfaces impair the runability of paper machines, because thick biofilms may break loose and cause web breaks or product defects such as holes and coloured spots (Blanco et al., The GenBank/EMBL/DDBJ accession numbers for the 16S rRNA gene sequences of strains A-col-R2A-4, C-lvk-R2A-2 T , C-R2A-52d, E-R2A-8a and C-lvk-R2A-1 are AJ505840 and AJ844281-AJ844284, respectively. Details of the polyamine and fatty acid profiles of the novel strains, characteristics that distinguish the strains from other similar species isolated from paper-machine biofilms, results of riboprint analysis and additional electron micrographs are available as supplementary material in IJSE...

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The genus Ammoniphilus is proposed for aerobic endospore-forming Gramvariable rod-shaped bacteria, which are ammonium-dependent, obligately oxa lotrop h ic and haloa I ka I i to lerant, oxidase-and catal ase-pos i t ive, mesop h i I ic and motile b y peritrichous flagella. Cell wall contained two electron-dense layers. The external layer consists of a chain of electron-dense granules morphologically resembling the cellulosomes of CIostridium thermocellum. Two species are described, Ammoniphilus oxalaticus gen. nov., sp. nov. and Ammoniphilus oxalivorans gen. nov., sp. nov. The type strains of these species are strains RAOx-1 (= DSM 11538) and RAOx-FS (= DSM 11537), respectively. Ammoniphilus strains were isolated from the rhizosphere of sorrel (Rumex acetosa) and from decaying wood. The strains require a high concentration of ammonium ions and use oxalate as the sole organic source of carbon and energy for growth; no growth factors were required. Growth occurred a t pH 6-8-9-5. The optimum temperature and pH for growth were 28-30 "C and 80-8.5. All strains grew in a saturated solution of ammonium oxalate, and tolerated 3 O/ O NaCI. Whole-cell hydrolysates contain meso-diaminopimelic acid and glucose. The menaquinone of the strains was MK 7, and the major cellular fatty acids were 12-methyl tetradecanoic, cis-hexadec-9-enoic and hexadecanoic acids. The G+C content of the DNA was 4 5 4 6 mol O/ O for A. oxalaticus and 42 mol O/ O for A. oxalivorans. The almost complete 165 rDNA sequence of three strains of the two species of Ammoniphilus shows that the genus falls into the radiation of the Clostridium-Bacillus subphylum of Grampositive bacteria. The closest phylogenetic neighbour of Ammoniphilus is Oxalophagus oxalicus. The DNA-DNA hybridization value between strains RAOx-1 and RAOx-FS was 3997%.

Biodegradability and compostability of nanofibrillar cellulose-based (NFC) products including films, concentrated NFC and paper products containing NFC were evaluated under controlled composting conditions. All the NFC products tested were biodegradable according to the requirements set in European standard EN 13432. NFC even enhanced the rate of biodegradability of paper containing 1.5 % NFC as an additive. Disintegration during composting was evaluated using the modified pilot-scale composting test EN 14045. NFC films disintegrated completely in 3 weeks of composting, and NFC did not influence the degradability of paper products containing NFC. Ecotoxicity during biodegradation of NFC products in a compost environment was evaluated using a bioluminescence test with Vibrio fischeri. No acute toxicity was detected for any of the samples.

In cells of Rhodococcus opacus GM-14, GM-29, and 1CP, the contents of branched (10-methyl) fatty acids increased from 3% to 15 to 34% of the total fatty acids when the cells were grown on benzene, phenol, 4-chlorophenol, chlorobenzene, or toluene as the sole source of carbon and energy, in comparison with cells grown on fructose. In addition, the content of trans-hexadecenoic acid increased from 5% to 8 to 18% with phenol or chlorophenol as the carbon source. The 10-methyl branched fatty acid content of R. opacus GM-14 cells increased in a dose-related manner following exposure to phenol or toluene when toluene was not utilized as the growth substrate. The results suggest that 10-methyl branched fatty acids may participate in the adaptation of R. opacus to lipophilic aromatic compounds.