Bremen Institute for Materials Testing

Bremen, Germany

Bremen Institute for Materials Testing

Bremen, Germany
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Freire M.T.,National Laboratory for Civil Engineering | Silva A.S.,National Laboratory for Civil Engineering | Veiga M.D.R.,National Laboratory for Civil Engineering | Brito J.D.,University of Lisbon | Schlutter F.,Bremen Institute for Materials Testing
Microscopy and Microanalysis | Year: 2016

In this paper the characterization of a gypsum plaster sample from the end of the 19th century simulating imperial red porphyry using a multi-analytical approach is presented and discussed. The results of X-ray diffraction (XRD), thermogravimetric and differential thermal analysis (TGA-DTA), physical and mechanical properties are summarized. In order to have further insight into the microstructure, polarized light microscopy (PLM), scanning electron microscopy coupled with energy dispersive X-ray spectrometer (SEM-EDS), and micro Raman spectroscopy analyzes were also made. They helped to clarify the main issues raised by the other complementary analytical techniques and allowed the establishment of interrelations between the different properties, providing important information about the materials, the skills, and the technological development involved in the art of imitating noble stones with gypsum pastes. This study also contributes to our knowledge concerning the preservation of these types of elements that are important in the context of European decorative arts and rarely reported in the literature. © Microscopy Society of America 2016.


Stantscheff R.,Johannes Gutenberg University Mainz | Kuever J.,Bremen Institute for Materials Testing | Rabenstein A.,Bremen Institute for Materials Testing | Seyfarth K.,Johannes Gutenberg University Mainz | And 2 more authors.
Applied Microbiology and Biotechnology | Year: 2014

In this study, methanogenic Archaea were isolated from five full-scale agricultural biogas plants (BGPs) located in Rhineland-Palatinate and Saarland, Germany, digesting maize silage and cattle manure. According to partial 16S rRNA gene sequences, the strains isolated from enrichment cultures were related to Methanoculleus bourgensis, Methanosarcina mazei, Methanosaeta concilii, and Methanobacterium formicicum. The 16S rRNA gene libraries of two representative BGPs screened with the direct amplified rDNA restriction analysis approach also revealed these Archaea to be present. Comparative phylogenetic analyses of reference strains and the isolates of genus Methanobacterium based on 16S and 23S rRNA gene sequences suggest two major groups of isolates, with both of them closely associated with Methanobacterium formicicum strain MFT. The affiliation of Methanobacterium isolates is further supported by denaturating gradient gel electrophoresis of 16S rRNA gene amplificates, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and specifically amplified polymorphic DNA-PCR (SAPD-PCR), a novel fingerprint approach applied to methanogenic Archaea for the first time. Signature sequence 03Mbf derived from the application of SAPD-PCR was subsequently used to develop a PCR-based primer system for the detection of Methanobacterium formicicum-related isolates and the reference strain in BGP samples. Amplification of 03Mbf fragments down to a minimal titer of 103 cells of Methanobacterium formicicum-related isolate Mb9 was possible under BGP fermenter-comparable conditions. © 2014 Springer-Verlag.


PubMed | National Laboratory for Civil Engineering, University of Lisbon and Bremen Institute for Materials Testing
Type: Journal Article | Journal: Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada | Year: 2016

In this paper the characterization of a gypsum plaster sample from the end of the 19th century simulating imperial red porphyry using a multi-analytical approach is presented and discussed. The results of X-ray diffraction (XRD), thermogravimetric and differential thermal analysis (TGA-DTA), physical and mechanical properties are summarized. In order to have further insight into the microstructure, polarized light microscopy (PLM), scanning electron microscopy coupled with energy dispersive X-ray spectrometer (SEM-EDS), and micro Raman spectroscopy analyzes were also made. They helped to clarify the main issues raised by the other complementary analytical techniques and allowed the establishment of interrelations between the different properties, providing important information about the materials, the skills, and the technological development involved in the art of imitating noble stones with gypsum pastes. This study also contributes to our knowledge concerning the preservation of these types of elements that are important in the context of European decorative arts and rarely reported in the literature.


Basen M.,Max Planck Institute for Marine Microbiology | Basen M.,University of Georgia | Kruger M.,Federal Institute for Geosciences and Natural Resources | Milucka J.,Max Planck Institute for Marine Microbiology | And 6 more authors.
Environmental Microbiology | Year: 2011

Anaerobic oxidation of methane (AOM) with sulfate is catalysed by microbial consortia of archaea and bacteria affiliating with methanogens and sulfate-reducing Deltaproteobacteria respectively. There is evidence that methane oxidation is catalysed by enzymes related to those in methanogenesis, but the enzymes for sulfate reduction coupled to AOM have not been examined. We collected microbial mats with high AOM activity from a methane seep in the Black Sea. The mats consisted mainly of archaea of the ANME-2 group and bacteria of the Desulfosarcina-Desulfococcus group. Cell-free mat extract contained activities of enzymes involved in sulfate reduction to sulfide: ATP sulfurylase (adenylyl:sulfate transferase; Sat), APS reductase (Apr) and dissimilatory sulfite reductase (Dsr). We partially purified the enzymes by anion-exchange chromatography. The amounts obtained indicated that the enzymes are abundant in the mat, with Sat accounting for 2% of the soluble mat protein. N-terminal amino acid sequences of purified proteins suggested similarities to the corresponding enzymes of known species of sulfate-reducing bacteria. The deduced amino acid sequence of PCR-amplified genes of the Apr subunits is similar to that of Apr of the Desulfosarcina/Desulfococcus group. These results indicate that the major enzymes involved in sulfate reduction in the Back Sea microbial mats are of bacterial origin, most likely originating from the bacterial partner in the consortium. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.


Koch T.,Isarstrasse 95 | Passman F.,Biodeterioration Control Associates, inc. | Rabenstein A.,Bremen Institute for Materials Testing
International Biodeterioration and Biodegradation | Year: 2015

Microbial activity is one of the primary causes of water-miscible metalworking fluid (MWF) deterioration in application. Although it is impractical to maintain MWF under microbe-free conditions, timely, accurate and easily interpreted microbial contamination condition can substantially reduce the risk of MWF biodeterioration. This paper compares different condition monitoring methods detecting the microbial contamination of MWF related to their speed and precision in laboratory and field samples. Two culture tests (plate count and dip-slides) and two adenosine triphosphate (ATP) test methods were compared. Additionally the matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-ToF-MS) is introduced as a method for the identification of bacterial strains isolated from MWF. The results clearly indicate that MWF monitoring is in need of standardization concerning sampling, area of measurement, and analysis of determinable cell counts as well as species communities. © 2014 Elsevier Ltd.


Blattel V.,Johannes Gutenberg University Mainz | Petri A.,Johannes Gutenberg University Mainz | Rabenstein A.,Bremen Institute for Materials Testing | Kuever J.,Bremen Institute for Materials Testing | Konig H.,Johannes Gutenberg University Mainz
Applied Microbiology and Biotechnology | Year: 2013

The genus Saccharomyces comprises very closely related species. This high degree of relationship makes a simple identification and differentiation of strains difficult since these species are hardly discriminable by their morphological and physiological features. A sequence analysis of ribosomal DNA and the corresponding internal transcribed spacers can only rarely be successfully applied. In this study, we proved the applicability of a novel DNA fingerprinting method, the SAPD-PCR (specifically amplified polymorphic DNA) and of MALDI-TOF-MS (matrix-assisted laser desorption ionization time-of-flight mass spectrometry) fingerprinting with the MALDI Biotyper for the differentiation of species belonging to the genus Saccharomyces. It was possible with SAPD-PCR to create specific banding patterns for all Saccharomyces species. Different strains of the same species produced nearly the same banding patterns. Specific and reproducible reference spectra could be generated for each of the strains with the MALDI Biotyper. Therefore, SAPD-PCR and MALDI-TOF-MS can be fast and reliable tools to identify these related Saccharomyces species which are applied in many biotechnological processes. © 2013 Springer-Verlag Berlin Heidelberg.


Gridneva E.,University of Voronezh | Chernousova E.,Russian Academy of Sciences | Dubinina G.,Russian Academy of Sciences | Akimov V.,Russian Academy of Sciences | And 3 more authors.
International Journal of Systematic and Evolutionary Microbiology | Year: 2011

Seven strains of the genus Sphaerotilus were obtained from natural thermal sulfide (strains D-501T, D-502, D-504, D-505 and D-507) and low-temperature ferrous (strain HST) springs and from an activated sludge system (strain D-380). These Sphaerotilus isolates and strains of Sphaerotilus natans obtained from the DSMZ (S. natans DSM 6575T, DSM 565 and DSM 566) were studied using a polyphasic taxonomic approach. All strains had Q-8 as the major quinone and C16: 1ω7, C16: 0 and C18: 1ω7 as the major fatty acids. The DNA-DNA hybridization results and 16S rRNA, hsp60 and gyrB gene sequencing experiments showed that isolates D-501T, D-502, D-504, D-505, D-507 and D-380 were closely related to the type strain of S. natans DSM 6575T. However, strains D-501T, D-502, D-504, D-505 and D-507 significantly differed from the heterotrophic strain S. natans DSM 6575T by their capability for lithotrophic growth with reduced sulfur compounds as an electron donor for energy conservation and some other phenotypic features. For this reason, strains D-501T, D-502, D-504, D-505 and D-507 merit a separate taxonomic classification at the subspecies level. The name Sphaerotilus natans subsp. sulfidivorans subsp. nov. (type strain D-501T = DSM 22545T = VKM B-2573T) is proposed. The subspecies Sphaerotilus natans subsp. natans subsp. nov. is automatically created as a result of this proposal. Strain D-380 was phenotypically closely related to S. natans DSM 6575T. Strains D-380 and S. natans DSM 6575T were assigned to the subspecies Sphaerotilus natans subsp. natans subsp. nov. (type strain DSM 6575T = ATCC 13338T). The 16S rRNA, hsp60 and gyrB gene sequences obtained for strains HST and DSM 565 showed very low sequence similarity values of 97.3%, 89.7% and 88.4%, respectively, with S. natans DSM 6575T. Strain HST shared 99% DNA-DNA relatedness with strain DSM 565 and 48% with S. natans DSM 6575T. The 16S rRNA, hsp60 and gyrB gene sequence similarities between strain DSM 566T and S. natans DSM 6575T were 97.5%, 91.5% and 87.0%, respectively. Strain DSM 566T had 52% DNA-DNA relatedness to S. natans DSM 6575T and shared 44% DNA-DNA similarity with strain HST. The creation of two novel species is proposed, Sphaerotilus montanus sp. nov. for strains HST and DSM 565 (type strain HST = DSM 21226T = VKM B-2519T) and Sphaerotilus hippei sp. nov. for strain DSM 566T (type strain DSM 566T = ATCC 29330T). Emended descriptions of the genus Sphaerotilus and of Sphaerotilus natans are presented. © 2011 IUMS.


Lavrinenko K.,University of Voronezh | Chernousova E.,Russian Academy of Sciences | Gridneva E.,University of Voronezh | Dubinina G.,Russian Academy of Sciences | And 4 more authors.
International Journal of Systematic and Evolutionary Microbiology | Year: 2010

A novel nitrogen-fixing strain, designated BV-ST, was isolated from a sulfur bacterial mat collected from a sulfide spring of the Stavropol Krai, North Caucasus, Russia. Strain BV-ST grew optimally at pH 7.5 and 37°C. According to the results of phylogenetic analysis, strain BV-ST belonged to the genus Azospirillum within the family Rhodospirillaceae of the class Alphaproteobacteria. Within the genus Azospirillum, strain BV-ST was most closely related to Azospirillum doebereinerae GSF71T, A. picis IMMIB TAR-3T and A. lipoferum ATCC 29707T (97.7, 97.7 and 97.4% 16S rRNA gene sequence similarity, respectively). DNA-DNA relatedness between strain BV-ST and A. doebereinerae DSM 13131T, A. picis DSM 19922T and A. lipoferum ATCC 29707T was 38, 55 and 42 %, respectively. Similarities between nifH sequences of strain BV-ST and members of the genus Azospirillum ranged from 94.5 to 96.8 %. Chemotaxonomic characteristics (quinone Q-10, major fatty acid C18:1ω7c and G+C content 67 mol%) were similar to those of members of the genus Azospirillum. In contrast to known Azospirillum species, strain BV-ST was capable of mixotrophic growth under microaerobic conditions with simultaneous utilization of organic substrates and thiosulfate as electron donors for energy conservation. Oxidation of sulfide was accompanied by deposits of sulfur globules within the cells. Based on these observations, strain BV-ST is considered as a representative of a novel species of the genus Azospirillum, for which the name Azospirillum thiophilum sp. nov. is proposed. The type strain is BV-ST (=DSM 21654T =VKM B-2513T). © 2010 IUMS.


PubMed | Bremen Institute for Materials Testing
Type: | Journal: Journal of microbiological methods | Year: 2015

Stachybotrys chartarum and Stachybotrys chlorohalonata are two closely related species. Unambiguous identification of these two species is a challenging task if relying solely on morphological criteria and therefore smarter and less labor-intensive approaches are needed. Here we show that even such closely related species of fungi as S. chartarum and S. chlorohalonata are unequivocally discriminated by their highly reproducible MALDI-TOF-MS fingerprints (matrix assisted laser desorption/ionization time-of-flight mass spectrometry fingerprints). We examined 19 Stachybotrys and one Aspergillus isolate by MALDI-TOF-MS. All but one isolate produced melanin containing conidia on malt extract agar. Mass spectra were obtained in good quality from the analysis of hyaline and darkly pigmented conidia by circumventing the property of melanin which causes signal suppression. MALDI-TOF fingerprint analysis clearly discriminated not only the two morphologically similar species S. chartarum and S. chlorohalonata from each other but separated them precisely from Stachybotrys bisbyi and Aspergillus versicolor isolates. Furthermore, even S. chartarum chemotypes A and S could be differentiated into two distinct groups by their MALDI-TOF fingerprints. The chemotypes of S. chartarum isolates were identified by trichodiene synthase 5 (tri5) sequences prior to mass spectra analysis. Additionally, species identities of all isolates were verified by their 18S rRNA and tri5 gene sequences.


PubMed | University of Veterinary Medicine Vienna, Justus Liebig University and Bremen Institute for Materials Testing
Type: Journal Article | Journal: International journal of systematic and evolutionary microbiology | Year: 2015

Two Gram-negative, rod-shaped, non-spore-forming bacteria, isolated from metal working fluids were investigated to determine their taxonomic positions. On the basis of 16S rRNA gene sequence phylogeny, both strains (MPA 1113(T) and MPA 1105(T)) formed a distinct cluster with 97.7% sequence similarity between them, which was in the vicinity of members of the genera Methylobacterium, Camelimonas, Chelatococcus, Bosea, Salinarimonas and Microvirga to which they showed low sequence similarities (below 94%). The predominant compounds in the polyamine pattern and in the quinone system of the two strains were spermidine and ubiquinone Q-10, respectively. The polar lipid profiles were composed of the major compounds: phosphatidylmonomethylethanolamine, phosphatidylglycerol, phosphatidylcholine, major or moderate amounts of diphosphatidylglycerol, two unidentified glycolipids and three unidentified aminolipids. Several minor lipids were also detected. The major fatty acids were either C19:0 cyclo 8c or C18:17c. The results of fatty acid analysis and physiological and biochemical tests allowed both, the genotypic and phenotypic differentiation of the isolates from each other, while the chemotaxonomic traits allowed them to be differentiated from the most closely related genera. In summary, low 16S rRNA gene sequence similarities and marked differences in polar lipid profiles, as well as in polyamine patterns, is suggestive of a novel genus for which the name Pseudochelatococcus gen. nov. is proposed. MPA 1113(T) (=CCM 8528(T)=LMG 28286(T)=CIP 110802(T)) and MPA 1105(T) (=CCM 8527(T)=LMG 28285(T)) are proposed to be the type strains representing two novel species within the novel genus, Pseudochelatococcus gen. nov., for which the names Pseudochelatococcus lubricantis sp. nov. and Pseudochelatococcus contaminans sp. nov. are suggested, respectively.

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