New Gammaproteobacteria were isolated from 3rd stage fly larvae of the parasitic fly Wohlfahrtia magnifica. Phylogenetic analysis of the new isolates showed that these bacteria belong to a distinct lineage close to Ignatzschineria larvae, which was originally isolated from the same species of fly. The low similarity values in 16S rRNA gene sequences (93.8–94.8 %), and differences in fatty acid profiles, RiboPrint patterns, MALDI-TOF mass spectra of cell extracts, and physiological and biochemical characteristics differentiate the isolates from the type strain of Ignatzschineria larvae (DSM 13226T), and indicate that our isolates represent a new genus within the Gammaproteobacteria. The major isoprenoid quinone of the strains is Q8, the major fatty acids are C18 : 1 and C14 : 0, and the predominant polar lipids are phosphatidylglycerol, phosphatidylethanolamine and phosphatidylserine. The G+C content of the DNA of the type strain is 44.3 mol%. The name Wohlfahrtiimonas chitiniclastica gen. nov., sp. nov., is proposed for this novel genus and species. The type strain is S5T (=DSM 18708T=CCM 7401T).

Three alkalitolerant bacterial strains were isolated from the surface of decomposing rhizomes of reed [Phragmites australis (Cav.) Trin. et Steudel] in Lake Fertő (Hungary). Cells of the novel isolates were Gram-negative, motile rods and formed star-shaped aggregates. They were facultatively anaerobic and chemo-organotrophic. Bacteriochlorophyll a was not synthesized under aerobic conditions. The strains were catalase and oxidase positive, produced acid from d-glucose under aerobic and anaerobic conditions and reduced nitrate to nitrogen. They tolerated pH values from 7·0 to 11·0 and grew in the absence of NaCl as well as in up to 5 % (w/v) NaCl. The G+C content of the DNA was 64·6 mol% and the major isoprenoid quinone was Q-10. The dominant cellular fatty acid was C18 : 1 ω7c. The cell membrane contained phosphatidyl glycerol, diphosphatidyl glycerol, phosphatidyl ethanolamine, phosphatidyl serine and one unknown phospholipid as polar lipids. Polyphasic taxonomic characterization revealed that strain C6/19T is most closely related to the Stappia–Roseibium cluster in the α-subclass of the Proteobacteria (showing 95·8–93·6 % 16S rDNA sequence similarity). According to the phylogenetic and phenotypic evidence presented, a new genus and species is proposed, Pannonibacter phragmitetus gen. nov., sp. nov. The type strain is C6/19T (=DSM 14782T=NCAIM B02025T).

Strains of a novel alphaproteobacterium were isolated from ultrapure water of a Hungarian power plant on a newly developed medium. Phylogenetic analysis of the 16S rRNA gene sequences of the novel strains showed that these bacteria belong to a distinct lineage far from any known taxa. Based on the 16S rRNA gene sequences, strains PI_31, PI_25 and PI_21^Texhibited the highest sequence similarity to Bosea minatitlanensis AMX51^T(93.43 %) and Bosea thiooxidans DSM 9653^T(93.36 %); similarity to all other taxa was less than 93.23 %. Fatty acid profiles, matrix-assisted laser-desorption/ionization time-of-flight mass spectra of cell extracts as well as physiological and biochemical characteristics indicated that our strains represent a novel genus and species within the class Alphaproteobacteria . The major isoprenoid quinone of the strains was Q-10, the major cellular fatty acids were C_18 : 1ω7cand 11-methyl C_18 : 1ω7cand the polar lipid profiles of the strains contained phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and several unknown phospholipids and other lipids. The characteristic diamino acid in their cell wall wasmeso-diaminopimelic acid. The G+C content of DNA of the proposed type strain PI_21^Twas 68.9 mol%. A new genus and species,Phreatobacter oligotrophusgen. nov., sp. nov., is proposed to accommodate the strains. Strain PI_21^T( = DSM 25521^T = NCAIM B 02510^T) is the type strain ofPhreatobacter oligotrophus.

The prokaryotic, generic name Schineria Tóth et al. 2001 is illegitimate owing to the prior existence of the name Schineria for a genus within the Diptera [Principle 2, Rule 51b(4) of the Bacteriological Code (1990 Revision)]. Therefore, a new genus name, Ignatzschineria gen. nov., is proposed for this taxon. As a result, a new combination is required for the type species, Ignatzschineria larvae comb. nov., to replace the illegitimate combination Schineria larvae Tóth et al. 2001 .

The diversity of biofilm bacterial communities associated with cave walls of the Buda Thermal Karst System (BTKS) located in Hungary was studied by scanning electron microscopy and molecular cloning based on 16S rRNA genes. Samples from two sites, the Molnár János cave (MJB) and the Rudas-Török spring cave (RTB), respectively, were analyzed and compared. The presence of iron precipitates was typical at both study sites, despite the fact that the cell morphological structure of the biofilms observed by SEM was characteristically different. Clones analyzed from BTKS were found to belong to 10 common phyla (Thermodesulfobacteria, Chloroflexi, Nitrospirae, Chlorobi, Proteobacteria, Firmicutes, Actinobacteria, Planctomycetes, Bacteroidetes, Verrucomicrobia) within the domain Bacteria. Moreover, sequences related to Aquificeae, Acidobacteria and Gemmatimonadetes were exclusive to MJB, while Cyanobacteria were found in RTB only. The phylogenetic distribution of the dominant bacterial clones was quite dissimilar between the two sites. In the biofilm from MJB clones affiliated with Firmicutes, whereas in the RTB clones related to Deltaproteobacteria were found in the highest number. In addition, substantially larger numbers of clone sequences related to thermophilic bacteria were recovered from MJB. On the basis of sequences of known microorganisms corresponding to our clone sequences, it is assumed that aerobic as well as anaerobic iron and sulfur transformation performed by different bacterial communities might be important biogenic processes in both caves.