Pseudomonas carbonaria sp. nov., isolated from charcoal.

A beige-pigmented, oxidase-positive bacterial isolate, Wesi-4T, isolated from charcoal in 2012, was examined in detail by applying a polyphasic taxonomic approach. Cells of the isolates were rod shaped and Gram-stain negative. Examination of the 16S rRNA gene sequence of the isolate revealed highest sequence similarities to the type strains of Pseudomonas matsuisoli and Pseudomonas nosocomialis (both 97.3 %). Phylogenetic analyses on the basis of the 16S rRNA gene sequences indicated a separate position of Wesi-4T, which was confirmed by multilocus sequence analyses (MLSA) based on the three loci gyrB, rpoB and rpoD and a core genome-based phylogenetic tree. Genome sequence based comparison of Wesi-4T and the type strains of P. matsuisoli and P. nosocomialis yielded average nucleotide identity values <95 % and in silico DNA-DNA hybridization values <70 %, respectively. The polyamine pattern contains the major amines putrescine, cadaverine and spermidine. The quinone system contains predominantly ubiquinone Q-9 and in the polar lipid profile diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine are the major lipids. The fatty acid contains predominantly C16 : 0, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and summed feature 8 (C18 : 1ω7c and/or C18 : 1 ω6c). In addition, physiological and biochemical tests revealed a clear phenotypic difference from P. matsuisoli. These cumulative data indicate that the isolate represents a novel species of the genus Pseudomonas for which the name Pseudomonas carbonaria sp. nov. is proposed with Wesi-4T (=DSM 110367T=CIP 111764T=CCM 9017T) as the type strain.

Flavobacterium panici sp. nov. isolated from the rhizosphere of the switchgrass Panicum virgatum.

A Gram-staining-negative non endospore-forming strain, PXU-55T, was isolated from the rhizosphere of the switchgrass Panicum virgatum and studied in detail to determine its taxonomic position. The results of 16S rRNA gene sequence analysis indicated that the isolate represented a member of the genus Flavobacterium. The isolate shared highest 16S rRNA gene sequence similarities with the type strains of Flavobacterium chungangense (98.78 %) and Flavobacterium chilense (98.64 %). The average nucleotide identity (ANI) and in silico DNA-DNA hybridization (isDDH) values between the PXU-55T genome assembly and the ones of the most closely related type strains of species of the genus Flavobacterium were 87.3 and 31.9% (Flavobacterium defluvii), and 86.1 and 29.9% (Flavobacterium johnsoniae). Menaquinone MK-6 was the major respiratory quinone. As major polar lipids, phosphatidylethanolamine, an ornithine lipid and the unidentified polar lipids L2, L3 and L4 lacking a functional group were found. Moderate to minor amounts of another ornithine lipid, the unidentified lipid L1 and a glycolipid were present, as well. The major polyamine is sym-homospermidine. The fatty acid profiles contained major amounts of iso-C15:0, iso-C15:0 3-OH, iso-C17:0 3-OH, C15:0, summed feature 3 (C16:1ω7c and/or iso-C15:0 2-OH) and various hydroxylated fatty acids in smaller amounts, among them iso C16:0 3-OH, C16:0 3-OH and C15:0 3-OH, which supported the classification of the isolate as a member of the genus Flavobacterium. Physiological and biochemical characterisation and ANI calculations with the type strains of the most closely related species allowed a clear phenotypic and genotypic differentiation of the strain. For this reason, we propose that strain PXU-55T (=CIP 111646T=CCM 8914T) represents a novel species with the name Flavobacterium panici sp. nov.

A review of bioinformatics platforms for comparative genomics. Recent developments of the EDGAR 2.0 platform and its utility for taxonomic and phylogenetic studies.

The rapid development of next generation sequencing technology has greatly increased the amount of available microbial genomes. As a result of this development, there is a rising demand for fast and automated approaches in analyzing these genomes in a comparative way. Whole genome sequencing also bears a huge potential for obtaining a higher resolution in phylogenetic and taxonomic classification. During the last decade, several software tools and platforms have been developed in the field of comparative genomics. In this manuscript, we review the most commonly used platforms and approaches for ortholog group analyses with a focus on their potential for phylogenetic and taxonomic research. Furthermore, we describe the latest improvements of the EDGAR platform for comparative genome analyses and present recent examples of its application for the phylogenomic analysis of different taxa. Finally, we illustrate the role of the EDGAR platform as part of the BiGi Center for Microbial Bioinformatics within the German network on Bioinformatics Infrastructure (de.NBI).

Development of a qualitative real-time PCR for microbiological quality control testing in mammalian cell culture production.

AIMS: The aim of this study was to develop and evaluate a real-time PCR technology for microbiological control methods to examine individualized cell therapeutics, an emerging class of pharmaceutical formulations. METHODS AND RESULTS: Oligonucleotide primers and hybridization probe for bacterial detection targeting the 16SrRNA gene were adapted based on Nadkarni et al. [Microbiology148 (2002) 257]. For detection of yeast and moulds, primers and probe were designed from conserved sequences of the 18SrRNA gene in this study. The real-time PCR assays were tested on genomic DNA of Escherichia coli and Candida albicans to assess efficiency and linear dynamic range. After successful establishment of robust real-time PCRs, applicability of the assays was evaluated by extracting microbial target DNA from cell-based preparations. Different commercial DNA extraction methods were compared identifying the MagNA Pure DNA Isolation Kit III as the method of choice. Sensitivity was examined for different strains and a detection limit of 102 -103 CFU per ml in a sample containing ~106 mammalian cells per ml was achieved. CONCLUSIONS: This study reports the successful establishment of two qualitative real-time PCR assays, enabling in general the broad-range detection of microbial contaminants in a cell-based sample matrix. SIGNIFICANCE AND IMPACT OF THE STUDY: Individualized cell therapeutics tend to have a short shelf life. Due to lengthy incubation periods, compendial testing according to current pharmacopoeial guidelines may not be applicable. We report a suitable alternative method upon which future microbiological quality control methods for such products could be based on. However, to implement valid rapid microbiological testing methods using real-time PCR technology, further challenges need to be addressed.

Bacterial diversity and antibiotic resistances of abundant aerobic culturable bacteria in input and output samples of 15 German biogas plants.

AIM: Determination of the diversities and antibiotic resistances of the most abundant aerobic culturable bacteria and their survival in 15 German biogas plants (BGPs). METHODS AND RESULTS: Microbiological standard media (complex and selective media) were applied to enumerate mesophilic and oligotrophic bacteria (Enterobacteriaceae, Salmonella, staphylococci and enterococci) in input and output samples of BGPs. Concentrations of aerobic culturable bacteria in outputs were mostly one to two orders of magnitude lower than in input samples. In total, 852 isolates from input and 902 from output samples were identified either by partial 16S rRNA gene sequencing or Matrix-assisted Laser Desorption/Ionization-Time of Flight (MALDI-TOF) analysis. Antibiotic resistance screening of target families against veterinary relevant antibiotics resulted in similar resistance pattern in input and output samples. CONCLUSIONS: Potentially pathogenic bacteria were detected in output samples of BGPs, but in decreased abundance. The selectivity of the most applied clinical standard media was insufficient. SIGNIFICANCE AND IMPACT OF THE STUDY: Only little is known about the release of antibiotic resistant and potentially pathogenic bacteria from BGPs. However, this study indicates the detection of several potentially pathogenic bacteria in output samples, which showed several antibiotic resistances.

Chelativorans intermedius sp. nov. and proposal to reclassify Thermovum composti as Chelativorans composti comb. nov.

Two Gram-stain-negative, non-endospore-forming, rod-shaped bacteria, strains CC-MHSW-5(T) and A1392, were isolated from water of coastal hot springs located in Taiwan and China, respectively, and investigated for their taxonomic position. The two strains shared identical 16S rRNA gene sequences, a DNA-DNA hybridization value >80% and similar genomic DNA G+C contents (64.3 and 64.6 mol%), but showed different genomic fingerprint patterns generated by BOX-PCR and three random amplification polymorphic DNA PCRs. The strains shared highest 16S rRNA gene sequence similarities with the type strains of Chelativorans multitrophicus (96.7 and 96.1%), Thermovum composti (96.2 and 96.1%) and Chelativorans oligotrophicus (96.1 and 95.8%). Phylogenetic trees (based on 16S rRNA and recA gene sequence comparisons) showed a distinct clustering of both strains with the type strains of species of the genus Chelativorans and T. composti Nis3(T). The quinone systems of strains CC-MHSW-5(T) and Nis3(T) contained ubiquinone Q-10 as the major component. The major polyamine in both strains was sym-homospermidine. Putrescine, spermidine and, for strain CC-MHSW-5(T), spermine were found in minor concentrations. Their polar lipid profiles consisted of phosphatidylmonomethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and diphosphatidylglycerol. The fatty acid profile contained major amounts of C18 : 1ω7c and C19 : 0 cyclo ω8c. On the basis of these results, the two strains are considered to represent a novel species of the genus Chelativorans , for which the name Chelativorans intermedius sp. nov. is proposed. The type strain is CC-MHSW-5(T) ( =CCM 8543(T) =LMG 28482(T) =DSM 29391(T) =CIP 110825(T)). Based on both genotypic and phenotypic characters, it is proposed that T. composti be reclassified within the genus Chelativorans as Chelativorans composti comb. nov.

Rhodococcus defluvii sp. nov., isolated from wastewater of a bioreactor and formal proposal to reclassify [Corynebacterium hoagii] and Rhodococcus equi as Rhodococcus hoagii comb. nov.

A Gram-stain-positive, non-endospore-forming rod-shaped bacterium, strain Ca11(T), was isolated from a bioreactor with extensive phosphorus removal and was studied in detail for its taxonomic allocation. 16S rRNA gene sequence analysis revealed closest sequence similarity of the strain to type strains of [Corynebacterium hoagii] and Rhodococcus equi (98.9%), Rhodococcus koreensis and Rhodococcus wratislaviensis (both 98.4%), Rhodococcus opacus and Rhodococcus canchipurensis (both 98.0%) followed by Rhodococcus kunmingensis and Rhodococcus imtechensis (97.7%). Phylogenetic trees showed a distinct clustering of strain Ca11(T) with the type strains of [C. hoagii], R. equi, and R. kunmingensis separate to all other species of the genus Rhodococcus. The quinone system of strain Ca11(T) was composed of dihydrogenated menaquinones with 8 (major amount) as well as 7 and 6 isoprenoid units [MK-8(H2), MK-7(H2), MK-6(H2)]. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside, one unknown phospholipid and an unidentified glycolipid. The fatty acid profile was similar to that reported for R. equi and contained major amounts of C16:0, C18:1ω9c and 10-methyl C18:0, supporting the allocation of the strain to the genus Rhodococcus. Physiological and biochemical characterization and DNA-DNA hybridization with type strains of the most closely related species allowed clear phenotypic and genotypic differentiation of the isolate. On the basis of these results, strain Ca11(T) ( = DSM 45893(T) = LMG 27563(T)) represents a novel species of the genus Rhodococcus, with the proposed name Rhodococcus defluvii sp. nov. In addition, a polyphasic taxonomic analysis of [Corynebacterium hoagii] DSM 20295(T) and Rhodococcus equi DSM 20307(T) indicated that the two strains belong to the same species, for which the name Rhodococcus hoagii comb. nov. takes priority, according to the Rules of the Bacteriological Code.

Methylobacterium trifolii sp. nov. and Methylobacterium thuringiense sp. nov., methanol-utilizing, pink-pigmented bacteria isolated from leaf surfaces.

Three pink-pigmented, aerobic, Gram-stain-negative, rod-shaped and facultatively methylotrophic strains were isolated from the phyllosphere of Trifolium repens and Cerastium holosteoides. 16S rRNA gene sequence analysis support the affiliation of all strains to the genus Methylobacterium. The closest relatives of strains C34(T) and T5 were Methylobacterium gnaphalii 23e(T) (98.0 and 98.5 % sequence similarity, respectively) and Methylobacterium organophilum JCM 2833(T) (97.0 and 97.2 %, respectively). Strain TA73(T) showed the highest sequence similarities to Methylobacterium marchantiae JT1(T) and Methylobacterium bullatum F3.2(T) (both 97.9 %), followed by Methylobacterium phyllosphaerae CBMB27(T) and Methylobacterium brachiatum DSM 19569(T) (both 97.8 %), Methylobacterium cerastii C15(T) and Methylobacterium radiotolerans JCM 2831(T) (both 97.7 %). The major components in the fatty acid profiles were C18 : 1ω7c, C16 : 0 and one unknown fatty acid for strain TA73(T) and C18 : 1ω7c, C16 : 1ω7c/iso-C15 : 0 2-OH, C18 : 0 and C16 : 0 for strains C34(T) and T5. Physiological and biochemical analysis, including DNA-DNA hybridization, revealed clear differences between the investigated strains and their closest phylogenetic neighbours. DNA-DNA hybridization studies also showed high similarities between strains C34(T) and T5 (59.6-100 %). Therefore, the isolates represent two novel species within the genus Methylobacterium, for which the names Methylobacterium trifolii sp. nov. (type strain TA73(T) = LMG 25778(T) = CCM 7786(T)) and Methylobacterium thuringiense sp. nov. (type strain C34(T) = LMG 25777(T) = CCM 7787(T)) are proposed.

Flavobacterium cutihirudinis sp. nov., isolated from the skin of the medical leech Hirudo verbana.

A Gram-staining-negative, non-endospore-forming, yellow-pigmented strain (E89(T)) was isolated from the skin of the medical leech Hirudo verbana obtained from a leech farm located in Biebertal, Germany. 16S rRNA gene sequencing analysis showed that the isolate was grouped in the genus Flavobacterium. Strain E89(T) was most closely related to Flavobacterium chilense LM-09-Fp(T) (98.2 %), Flavobacterium chungangense CJ7(T) (98.1 %), and Flavobacterium oncorhynchi 631-08(T) (98.1 %). 16S rRNA gene sequence similarities to all other species of the genus Flavobacterium were ≤ 97.4 %. A menaquinone of the type MK-6 was found to be the predominant respiratory quinone and the polar lipid profile consisted of the major compounds phosphatidylethanolamine, phosphatidylserine, two unidentified aminolipids, one unknown phospholipid and two unknown lipids. The fatty acid profile was composed of iso-C15 : 0, C15 : 0, summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH) found in major amounts and several hydroxylated fatty acids in smaller amounts, among them iso-C15 : 0 3-OH and iso-C17 : 0 3-OH. All these data support the allocation of the isolate in the genus Flavobacterium. Physiological/biochemical characterization and DNA-DNA hybridizations with the type strains of the most closely related species allowed a clear phenotypic and genotypic differentiation of the strain. Based on these data, strain E89(T) represents a novel species of the genus Flavobacterium, for which the name Flavobacterium cutihirudinis sp. nov. is proposed. The type strain is E89(T) (= DSM 25795(T) = LMG 26922(T) = CIP 110374(T)).

Ornithinimicrobium murale sp. nov., isolated from an indoor wall colonized by moulds.

A Gram-positive, non-spore-forming actinobacterium (01-Gi-040(T)) isolated from an indoor wall was studied to examine its taxonomic position. The isolate formed a very rudimentary substrate-mycelium that fragmented into rod-shaped to coccoid cells. On the basis of the 16S rRNA gene sequence similarity studies, strain 01-Gi-040(T) was shown to belong to the genus Ornithinimicrobium closely related to Ornithinimicrobium kibberense K22-20(T) (97.1 %), Ornithinimicrobium humiphilum DSM 12362(T) (96.2 %) and Ornithinimicrobium pekingense LW6(T) (96.1 %). A close relationship was also found with Arsenicicoccus bolidensis CCUG 47306(T) (95.9 %) and Arsenicicoccus piscis Kis4-19(T) (95.7 %) and a moderate relationship to the type strains of the genus Serinicoccus (94.0-94.1 %). The predominant menaquinone of strain 01-Gi-040(T) was MK-8(H(4)). The peptidoglycan contained ornithine as the diagnostic diamino acid. The polar lipid profile consisted of the lipids phosphatidylinositol, phosphatidylglycerol, diphosphatidylglycerol, an unknown phospholipid, an unknown aminolipid and two unknown phosphoglycolipids. The major fatty acids iso-C(15 : 0), iso-C(16 : 0) and iso-C(17 : 0) were consistent with the fatty acid patterns reported for members of the genus Ornithinimicrobium. The results of DNA-DNA hybridizations, physiological and biochemical tests allowed phenotypic differentiation of strain 01-Gi-040(T) from the three recognized species of the genus Ornithinimicrobium. Strain 01-Gi-040(T) represents a novel species of the genus Ornithinimicrobium, for which we propose the name Ornithinimicrobium murale sp. nov., with the type strain 01-Gi-040(T) (= DSM 22056(T) = CCM 7610(T)).

Ruegeria intermedia sp. nov., a moderately thermophilic bacterium isolated from a coastal hot spring.

A cream-coloured, Gram-negative, aerobic, non-motile moderately thermophilic, rod-to-irregular-shaped bacterium, CC-GIMAT-2(T), was isolated from a coastal hot spring of Green Island (Lutao), located off Taituang, Taiwan, on marine agar 2216. The 16S rRNA gene sequence analysis and subsequent comparisons showed that it was placed into the genus Ruegeria with 97.4 % similarity to Ruegeria lacuscaerulensis ITI-1157(T), and a lower sequence similarity to all other species of the genus Ruegeria. Reconstruction of phylogenetic trees indicated that strain CC-GIMAT-2(T) clustered within the genus Ruegeria. Robust tree topology for the genus Ruegeria including the new strain was only obtained by including all Rhodobacteraceae type strains but not if the analysis was limited to few selected taxa. The quinone system contained exclusively ubiquinone Q-10 and the fatty acid profile consisted mainly of C18 : 1ω7c, 11-methyl C18 : 1ω7c and C12 : 0 3-OH. The predominant polar lipids were diphosphatidylglycerol, phosphatidylglycerol and an unidentified aminolipid. Other lipids were detected in moderate to minor amounts. The characteristic feature of the polyamine pattern was the predominant triamine spermidine. On the basis of the 16S rRNA gene sequence analysis and of the chemotaxonomic and physiological data, strain CC-GIMAT-2(T) represents a novel species of the genus Ruegeria, for which the name Ruegeria intermedia sp. nov. is proposed. The type strain is CC-GIMAT-2(T) ( = CCUG 59209(T) = LMG 25539(T) = CCM 7758(T)).