Károly Márialigeti

Eötvös Loránd University, Budapeŝto, Budapest, Hungary

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Publications (120)212.37 Total impact

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    ABSTRACT: Naturally occurring and anthropogenic petroleum hydrocarbons are potential carbon sources for many bacteria. The AlkB-related alkane hydroxylases, which are integral membrane non-heme iron enzymes, play a key role in the microbial degradation of many of these hydrocarbons. Several members of the genus Rhodococcus are well-known alkane degraders and are known to harbor multiple alkB genes encoding for different alkane 1-monooxygenases. In the present study, 48 Rhodococcus strains, representing 35 species of the genus, were investigated to find out whether there was a dominant type of alkB gene widespread among species of the genus that could be used as a phylogenetic marker. Phylogenetic analysis of rhodococcal alkB gene sequences indicated that a certain type of alkB gene was present in almost every member of the genus Rhodococcus. These alkB genes were common in a unique nucleotide sequence stretch absent from other types of rhodococcal alkB genes that encoded a conserved amino acid motif: WLG(I/V/L)D(G/D)GL. The sequence identity of the targeted alkB gene in Rhodococcus ranged from 78.5 to 99.2% and showed higher nucleotide sequence variation at the inter-species level compared to the 16S rRNA gene (93.9-99.8%). The results indicated that the alkB gene type investigated might be applicable for: (i) differentiating closely related Rhodococcus species, (ii) properly assigning environmental isolates to existing Rhodococcus species, and finally (iii) assessing whether a new Rhodococcus isolate represents a novel species of the genus. Copyright © 2014 Elsevier GmbH. All rights reserved.
    Systematic and Applied Microbiology 11/2014; · 3.29 Impact Factor
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    ABSTRACT: The Buda Thermal Karst System is an active hypogenic karst area that offers possibility for the analysis of biogenic cave formation. The aim of the present study was to gain information about morphological structure and genetic diversity of bacterial communities inhabiting the Diana-Hygieia Thermal Spring (DHTS). Using scanning electron microscopy, metal accumulating and unusual reticulated filaments were detected in large numbers in the DHTS biofilm samples. The phyla Actinobacteria, Firmicutes and Proteobacteria were represented by both bacterial strains and molecular clones but phyla Acidobacteria, Chlorobi, Chlorofexi, Gemmatimonadetes, Nitrospirae and Thermotogae only by molecular clones which showed the highest similarity to uncultured clone sequences originating from different environmental sources. The biofilm bacterial community proved to be somewhat more diverse than that of the water sample and the distribution of the dominant bacterial clones was different between biofilm and water samples. The majority of biofilm clones was affiliated with Deltaproteobacteria and Nitrospirae while the largest group of water clones was related to Betaproteobacteria. Considering the metabolic properties of known species related to the strains and molecular clones from DHTS, it can be assumed that these bacterial communities may participate in the local sulphur and iron cycles, and contribute to biogenic cave formation.
    Acta Microbiologica et Immunologica Hungarica 09/2014; 61(3):329-346. · 0.65 Impact Factor
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    ABSTRACT: A preliminary study was conducted to compare the community level physiological profile (CLPP) and genetic diversity of rhizosphere microbial communities of four plant species growing nearby Kiskunság soda ponds, namely Böddi-szék, Kelemen-szék and Zab-szék. CLPP was assessed by MicroResp method using 15 different substrates while Denaturing Gradient Gel Electrophoresis (DGGE) was used to analyse genetic diversity of bacterial communities. The soil physical and chemical properties were quite different at the three sampling sites. Multivariate statistics (PCA and UPGMA) revealed that Zab-szék samples could be separated according to their genetic profile from the two others which might be attributed to the geographical location and perhaps the differences in soil physical properties. Böddi-szék samples could be separated from the two others considering the metabolic activity which could be explained by their high salt and low humus contents. The number of bands in DGGE gels was related to the metabolic activity, and positively correlated with soil humus content, but negatively with soil salt content. The main finding was that geographical location, soil physical and chemical properties and the type of vegetation were all important factors influencing the metabolic activity and genetic diversity of rhizosphere microbial communities.
    Acta Microbiologica et Immunologica Hungarica 09/2014; 61(3):347-361. · 0.65 Impact Factor
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    ABSTRACT: Geothermal wells characterized by thermal waters warmer than 30°C can be found in more than 65% of the area of Hungary. The examined thermal wells located nearby Szarvas are used for heating industrial and agricultural facilities because of their relatively high hydrocarbon content. The aim of this study was to reveal the prokaryotic community structure of the water of SZR18, K87 and SZR21 geothermal wells using molecular cloning methods and Denaturing Gradient Gel Electrophoresis (DGGE). Water samples from the outflow pipes were collected in 2012 and 2013. The phylogenetic distribution of archaeal molecular clones was very similar in each sample, the most abundant groups belonged to the genera Methanosaeta, Methanothermobacter and Thermofilum. In contrast, the distribution of bacterial molecular clones was very diverse. Many of them showed the closest sequence similarities to uncultured clone sequences from similar thermal environments. From the water of the SZR18 well, phylotypes closely related to genera Fictibacillus and Alicyclobacillus (Firmicutes) were only revealed, while the bacterial diversity of the K87 well water was much higher. Here, the members of the phyla Thermodesulfobacteria, Proteobacteria, Nitrospira, Chlorobi, OP1 and OPB7 were also detected besides Firmicutes.
    Acta Microbiologica et Immunologica Hungarica 09/2014; 61(3):363-377. · 0.65 Impact Factor
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    ABSTRACT: Bacterial communities of a bank-filtered drinking water system were investigated by aerobic cultivation and clone library analysis. Moreover, bacterial communities were compared using sequence-aided terminal restriction fragment length polymorphism (T-RFLP) fingerprinting at ten characteristic points located at both the collecting and the distributing part of the water supply system. Chemical characteristics of the samples were similar, except for the presence of chlorine residuals in the distribution system and increased total iron concentration in two of the samples. Assimilable organic carbon (AOC) concentration increased within the collection system, it was reduced by chlorination and it increased again in the distribution system. Neither fecal indicators nor pathogens were detected by standard cultivation techniques. Chlorination reduced bacterial diversity and heterotrophic plate counts. Community structures were found to be significantly different before and after chlorination: the diverse communities in wells and the collection system were dominated by chemolithotrophic (e.g., Gallionella and Nitrospira) and oligocarbophilic–heterotrophic bacteria (e.g., Sphingomonas, Sphingopyxis, and Bradyrhizobium). After chlorination in the distribution system, the most characteristic bacterium was related to the facultative methylotrophic Methylocella spp. Communities changed within the distribution system too, Mycobacterium spp. or Sphingopyxis spp. became predominant in certain samples.
    Journal of Basic Microbiology 05/2014; · 1.20 Impact Factor
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    ABSTRACT: A new bacterium, PB3-7BT, was isolated on phenol-supplemented inorganic growth medium from a laboratory-scale wastewater purification system that treated coke plant effluent. The 16S rRNA gene sequence analysis revealed that strain PB3-7BT belonged to the family Alcaligenaceae and possessed the highest pairwise similarity values to Parapusillimonas granuli LMG 24012T (97.5%), Candidimonas bauzanensis DSM 22805T (97.3%) and Pusillimonas noertemannii DSM 10065T (97.2%). Strain PB3-7BT was rod-shaped, motile, oxidase and catalase positive. The predominant fatty acids were C16:0 (38.8%), cycloC17:0 (20.7%), cycloC19:0ω8c (16.9%), and C14:0 3-OH (10.3%), and the major respiratory quinone was Q-8. The G + C content of the genomic DNA of strain PB3-7BT was 59.7 mol%. The new bacterium can be distinguished from the closely related type strains based on its positive urease activity and capability for the assimilation of glycerol and amygdalin. On the basis of the phenotypic, chemotaxonomic and molecular data, strain PB3-7BT is considered to represent a new genus and species, for which the name Eoetvoesia caeni gen. nov., sp. nov. is proposed. The type strain is PB3-7BT (=DSM 25520T=NCAIM B 02512T).
    INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY 02/2014; · 2.11 Impact Factor
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    ABSTRACT: The effect of vertical physico-chemical stratification on the planktonic microbial community composition of the deep, hypersaline and heliothermal Lake Ursu (Sovata, Romania) was examined in this study. On site and laboratory measurements were performed to determine the physical and chemical variables of the lake water, and culture-based and cultivation-independent techniques were applied to identify the members of microbial communities. The surface of the lake was characterized by a low salinity water layer while the deepest region was extremely saline (up to 300 g/L salinity). Many parameters (e.g. photosynthetically active radiation, dissolved oxygen concentration, pH, redox potential) changed dramatically from 2 to 4 m below the water surface in conjunction with the increasing salinity values. The water temperature reached a maximum at this depth. At around 3 m depth, there was a water layer with high (bacterio) chlorophyll content dominated by Prosthecochloris vibrioformis, a phototrophic green sulfur bacterium. Characteristic microbial communities with various prokaryotic taxa were identified along the different environmental parameters present in the different water layers. Some of these bacteria were known to be heterotrophic and therefore may be involved in the decomposition of lake organic material (e.g. Halomonas, Idiomarina and Pseudoalteromonas) while others in the transformation of sulfur compounds (e.g. Prosthecochloris). Eukaryotic microorganisms identified by molecular methods in the lake water belonged to genera of green algae (Mantionella and Picochlorum), and were restricted mainly to the upper layers.
    Extremophiles 02/2014; · 2.20 Impact Factor
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    ABSTRACT: The results of 16S rRNA, catA and gyrB gene sequence comparisons and reasserted DNA-DNA hybridization clearly indicated that Rhodococcus jialingiae Wang et al. 2010 (Wang, Z., Xu, J., Li, Y., Wang, K., Wang, Y., Hong, Q., Li, W.J. & Li, S.P. Int. J. Syst. Evol. Microbiol. 60:378-381, 2010) and Rhodococcus qingshengii Xu et al. 2007 (Xu, J.L., He, J., Wang, Z.C., Wang, K., Li, W.J., Tang, S.K. & Li, S.P. Int. J. Syst. Evol. Microbiol. 57:2754-2757, 2007) represent a single species. On the basis of priority R. jialingiae must be considered a later synonym of R. qingshengii.
    INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY 01/2014; 64(1):298-301. · 2.11 Impact Factor
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    ABSTRACT: Winter phytoplankton communities in the shallow alkaline pans of Hungary are frequently dominated by picoeukaryotes, sometimes in particularly high abundance. In winter 2012, the ice-covered alkaline Zab-szék pan was found to be extraordinarily rich in picoeukaryotic green algae (42-82 × 10(6) cells ml(-1)) despite the simultaneous presence of multiple stressors (low temperature and light intensity with high pH and salinity). The maximum photosynthetic rate of the picoeukaryote community was 1.4 μg C μg chlorophyll a (-1) h(-1) at 125 μmol m(-2) s(-1). The assimilation rates compared with the available light intensity measured on the field show that the community was considerably light-limited. Estimated areal primary production was 180 mg C m(-2) d(-1). On the basis of the 18S rRNA gene analysis (cloning and DGGE), the community was phylogenetically heterogeneous with several previously undescribed chlorophyte lineages, which indicates the ability of picoeukaryotic communities to maintain high genetic diversity under extreme conditions.
    Extremophiles 11/2013; · 2.20 Impact Factor
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    ABSTRACT: Strains of a novel Alphaproteobacterium were isolated from the ultrapure water of a Hungarian power plant on a newly developed medium. Phylogenetic analysis of the new 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_21T exhibit the highest sequence similarity values to Bosea minatitlanensis AMX51T (93.43%) and to Bosea thiooxidans DSM 9653T(93.36%), similarity to all other taxa is less than 93.23%. Fatty acid profiles, MALDI-TOF mass spectra of cell extracts as well as physiological and biochemical characteristics indicate that our strains represent a novel genus and species within the Alphaproteobacteria. The major isoprenoid quinone of the strains is Q-10, the major cellular fatty acids are C18:1w7c and 11Me18:1w7c, the polar lipid profile of strains contains phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and several unknown phospholipids and other lipids. The characteristic diamino acid in their cell wall is meso-diaminopimelic acid. The G+C content of DNA of the type strain is 68.9 mol%. PI_21T (=DSM 25521T =NCAIM B 02510T) is proposed as type strain of the new genus and species, Phreatobacter oligotrophus.
    INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY 11/2013; · 2.11 Impact Factor
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    ABSTRACT: A Gram-negative, rod-shaped bacterium, designated strain ERB1-3T, was isolated from a laboratory-scale activated sludge system treating coke plant effluent using thiocyanate-supplemented growth medium. Strain ERB1-3T was oxidase positive, weakly catalase positive and motile. The predominant fatty acids were C18:1ω7c and C17:1ω6c, and the major respiratory quinone was Q-10. Polar lipids were dominated by sphingoglycolipid and phosphatidylglycerol. The G + C content of the genomic DNA of strain ERB1-3T was 66.4 mol%. Based on the 16S rRNA gene, strain ERB1-3T exhibited the highest sequence similarity values to Sphingomonas sanxanigenens DSM 19645T (96.1%), Sphingobium scionense DSM 19371T (95.1%) and Stakelama pacifica LMG 24686T (94.8%) within the family Sphingomonadaceae (Alphaproteobacteria). The new isolate had some unique chemotaxonomic features that differentiated it from these closely related strains, contained the fatty acid cycloC19:0ω8c and possessed diphosphatidylglycerol only in trace amounts. On the basis of the phenotypic, chemotaxonomic and molecular data, strain ERB1-3T is considered to represent a novel genus and species, for which the name Hephaestia caeni gen. nov., sp. nov. is proposed. The type strain is ERB1-3T (=DSM 25527T=NCAIM B 02511T).
    INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY 11/2013; · 2.11 Impact Factor
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    ABSTRACT: In Hungary, the replacement of geothermal waters previously utilized for industrial purposes is still not resolved. As a workaround, they are usually released to natural surface waters after being stored in reservoirs. Our investigation focused on the Barex Reservoir System near Szarvas which consists of four separate, but interconnected artificial water bodies. According to the water chemical analysis, the utilized thermal water was anaerobic, alkaline, rich in phenol derivatives and was of high salinity. Since little is known about the microbiological properties of these types of environments, the aim of this study was to gain insight to the structure and composition of microbial communities and the influence of changing parameters. The first step of this long-term investigation was to reveal the phylogenetic diversity of microbial communities inhabiting the first lake water, sediment and biofilm developed on the reed surface. The spatial and temporal changes were tracked by DGGE, using primers 27fGC and 519r. Exploration of the phylogenetic diversity of bacteria and archaea was carried out by the construction of three clone libraries respectively, and sequencing 16S rRNA coding regions of DNA. Archaeal diversity was examined by the cloning of ribosomal sequences from the community DNA using primers A109f and A958r. Analyses have shown that bacterial communities of the sediment formed separate groups which showed little similarity to the communities of the lake water during the whole year. Both clone library analyses and DGGE patterns have shown that the influent water differed from every other sample. In the case of water samples, representatives of the Phylum Cyanobacteria were present in large proportions. Arthrospira platensis proved to be a constant member of the lake water community. In both biofilm and sediment samples members of the Genus Hydrogenophaga (Proteobacteria), the Ordines Rhodocyclales and Rhodobacterales and purple non-sulfur bacteria were found to be dominant. Archaeal communities were less diverse than bacterial ones based on the processing of three clone libraries and the similarity was more pronounced between the sample types. The archaeal diversity of the sediment was the most diverse among the sample types. The most common archaeal genera were Metanosaeta and Metanocalculus. The majority of bacteria identified from the Barex Reservoir-System was haloalkalophilic, and might be capable of utilizing a wide range of carbon compounds.
    4th Central European Forum for Microbiology, Keszthely, Hungary; 10/2013
  • Source
    Power of Microbes in Industry and Environment, Primosten, Croatia; 10/2013
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    ABSTRACT: Because of the selectivity of the commonly used media it is very difficult to cultivate bacteria inhabiting ultrapure waters under laboratory conditions. In this study 5 new media (synthetic and complex) were developed to reveal bacterial community of the ultrapure water originated from the water purification system of a Hungarian power plant which was studied already with using traditional media. Composition of the new media tends to reproduce the nutrient deficient conditions of the investigated water, therefore media were highly oligotrophic. Altogether 122 bacterial strains were isolated from the 5 different media. Based on ARDRA grouping 27 strains were chosen for the partial 16S rRNA gene sequence analysis. The results showed that the applied media strongly influence the composition of the cultivable bacterial community. A larger scale of α-Proteobacteria (Mesorhizobium spp., Ancylobacter sp., Methylobacterium sp.) and many Actinobacteria (Leifsonia sp., Microbacterium spp., Mycobacterium spp.) could be isolated from the same ultrapure water system than with any other cultivation methods or media applied before. Moreover, two novel bacterial taxa could be isolated from the studied water purification system.
    Acta Microbiologica et Immunologica Hungarica 09/2013; 60(3):345-57. · 0.65 Impact Factor
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    ABSTRACT: The effect of several easily degradable substrates, such as protein, starch and sunflower oil was investigated on the bacterial community of a laboratory-scale biogas model system. Besides measuring gas yield, Denaturing Gradient Gel Electrophoresis (DGGE), Phospholipids Fatty Acid Analysis (PLFA) for Bacteria and T-RFLP analysis of the mcrA gene for Archaea were used. The community of the examined biogas reactors adapted to the new substrates through a robust physiological reaction followed by moderate community abundance shifts. Gas yield data clearly demonstrated the physiological adaptation to substrate shifts. Statistical analysis of DNA and chemotaxonomic biomarkers revealed community abundance changes. Sequences gained from DGGE bands showed the dominance of the phyla Bacteroidetes and the presence of Firmicutes (Clostridia) and Thermotogae. This was supported by the detection of large amounts of branched 15-carbon non-hydroxy fatty acids in PLFA profiles, as common PLFA markers of the Bacteroidetes group. Minor abundance ratios changes were observed in the case of Archaea in accordance with changes of the fed substrates.
    Acta Microbiologica et Immunologica Hungarica 09/2013; 60(3):289-301. · 0.65 Impact Factor
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    ABSTRACT: In this study, changes in the bacterial community composition of the well waters of Harkány Spa were examined. Physical and chemical properties of mixing subsurface cold and thermal karst waters were correlated to shifts in bacterial community structures analyzed by denaturing gradient gel electrophoresis (DGGE) and principal component analysis (PCA). In addition, mineral components of the pellets were investigated by scanning electron microscopy. Samples from the effluent waters of Büdöstapolca I and II, Matty and Thermal VI wells were taken seasonally in 2007 and 2008. The comparison of the results of DGGE and PCA analyses showed that bacterial communities from the Büdöstapolca wells were distinct from those of Matty and Thermal VI, but seasonal changes were not detected. According to the phylogenetic analysis of the excised DGGE bands, presence of chemolithotrophic Proteobacteria (Thiobacillus, Thiothrix, and distant relatives of Sulfurospirillum) were typical in the Büdöstapolca wells, while members of Actinobacteria (Plantibacter, Actinobacterium, Microbacterium) and Firmicutes (Planococcus) were characteristic to the Matty and Thermal VI wells. In the pellets pyrite framboid crystals were observed by electron microscopy, which are minerals known to be biologically induced by dissimilatory iron- and sulfur (sulfate)-reducing bacteria.
    Acta Microbiologica et Immunologica Hungarica 09/2013; 60(3):329-43. · 0.65 Impact Factor
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    ABSTRACT: Lake Hévíz is the largest natural warm water lake of Europe. The curative mud of the lake comprises volcanic and marsh components although their species composition is hardly known yet. The aim of the present study was to gain information about the distribution and species diversity of bacterial communities inhabiting the sediment of Lake Hévíz using cultivation-based and molecular cloning methods. Samples from two depths and locations were taken in 2004 and 2007. Representatives of the altogether 255 bacterial isolates were affiliated with the phyla Firmicutes, Actinobacteria, Proteobacteria and Bacteroidetes. The most abundant groups belonged to the genus Bacillus (Firmicutes). Many of Lake Hévíz isolates showed the highest sequence similarity to bacteria known to be plant associated or members of normal human microbiota as well as participating in decomposition of highly resistant organic materials. In the three clone libraries, phylotypes belonging to altogether different phyla (Firmicutes, Actinobacteria, Proteobacteria, Bacteroidetes, Cyanobacteria, Chlorobi, Chloroflexi, Deferribacteres, Nitrospirae, Spirochaetes and Verrucomicrobia) were revealed from which members of Gammaproteobacteria and Cyanobacteria proved to be the most abundant. Regardless of the sampling times and methodology used, high spatial heterogeneities of bacterial community structures were characteristic of the sediment of Lake Hévíz.
    Acta Microbiologica et Immunologica Hungarica 06/2013; 60(2):211-235. · 0.65 Impact Factor
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    ABSTRACT: Nowadays, because of substantial use of petroleum-derived fuels the number and extension of hydrocarbon polluted terrestrial ecosystems is in growth worldwide. In remediation of aforementioned sites bioremediation still tends to be an innovative, environmentally attractive technology. Although huge amount of information is available concerning the hydrocarbon degradation potential of cultivable hydrocarbonoclastic bacteria little is known about the in situ long-term effects of petroleum derived compounds on the structure of soil microbiota. Therefore, in this study our aim was to determine the long-term impact of total petroleum hydrocarbons (TPHs), volatile petroleum hydrocarbons (VPHs), total alkyl benzenes (TABs) as well as of polycyclic aromatic hydrocarbons (PAHs) on the structure of bacterial communities of four different contaminated soil samples. Our results indicated that a very high amount of TPH affected positively the diversity of hydrocarbonoclastic bacteria. This finding was supported by the occurrence of representatives of the α-, β-, γ-Proteobacteria, Actinobacteria, Flavobacteriia and Bacilli classes. High concentration of VPHs and TABs contributed to the predominance of actinobacterial isolates. In PAH impacted samples the concentration of PAHs negatively correlated with the diversity of bacterial species. Heavily PAH polluted soil samples were mainly inhabited by the representatives of the β-, γ-Proteobacteria (overwhelming dominance of Pseudomonas sp.) and Actinobacteria.
    World Journal of Microbiology and Biotechnology 04/2013; 29(11):1989-2002. · 1.35 Impact Factor
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    ABSTRACT: Böddi-szék is one of the shallow soda ponds located in the Kiskunság National Park, Hungary. In June 2008, immediately prior to drying out, an extensive algal bloom dominated by a green alga (Oocystis submarina Lagerheim) was observed in the extremely saline and alkaline water of the pond. The aim of the present study was to reveal the phylogenetic diversity of the bacterial communities inhabiting the water of Böddi-szék during the blooming event. Using two different selective media, altogether 110 aerobic bacterial strains were cultivated. According to the sequence analysis of the 16S rRNA gene, most of the strains belonged to alkaliphilic or alkalitolerant and moderately halophilic species of the genera Bacillus and Gracilibacillus (Firmicutes), Algoriphagus and Aquiflexum (Bacteroidetes), Alkalimonas and Halomonas (Gammaproteobacteria). Other strains were closely related to alkaliphilic and phototrophic purple non-sulfur bacteria of the genera Erythrobacter and Rhodobaca (Alphaproteobacteria). Analysis of the 16S rRNA gene-based clone library indicated that most of the total of 157 clone sequences affiliated with the anoxic phototrophic bacterial genera of Rhodobaca and Rhodobacter (Alphaproteobacteria), Ectothiorhodospira (Gammaproteobacteria) and Heliorestis (Firmicutes). Phylotypes related to the phylum Bacteroidetes formed the second most abundant group. Clones related to the mainly anaerobic and alkaliphilic bacterial genera of Anoxynatronum (Firmicutes), Spirochaeta (Spirochaetes) and Desulfonatronum (Deltaproteobacteria) were also abundant. Further clone sequences showed less than 95 % similarity values to cultivated species of the phyla Actinobacteria, Cyanobacteria, Deinococcus-Thermus, Fibrobacteres, Gemmatimonadetes and Lentisphaerae.
    Extremophiles 04/2013; · 2.20 Impact Factor
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    ABSTRACT: ‘Chlorella’ and ‘Nannochloris’ were traditional genera of minute coccoid green algae with numerous species described in the past century, including isolates used as experimental test organisms. In the last few years, the introduction of DNA-based phylogenetic analyses resulted in a large number of taxonomic revisions. We investigated and reclassified a taxonomically problematic group within the Trebouxiophyceae (comprising ‘Nannochloris eucaryotum’ UTEX 2502, ‘N. eucaryotum’ SAG 55.87 and ‘Chlorella minutissima’ SAG 1.80), distantly related to the recently described Chloroparva isolates (97.5–97.9 % 18S rRNA gene pairwise similarity). Cryopreserved material of SAG 55.87 was selected as holotype for a novel species – Pseudochloris wilhelmii Somogyi, Felföldi & Vörös – whose phylogenetic position confirmed the proposal of a new genus. Pseudochloris wilhelmii had spherical to oval cells with an average diameter of 2.6 × 2.8 µm and a simple ultrastructure characteristic of small green algae. Vegetative cells sometimes contained several lipid droplets occupying a large portion of the cells. The cell wall consisted of an outer trilaminar layer and an inner microfibrillar sheet. Cells divided by autosporulation, forming two or four daughter cells per autosporangium. The pigment composition was typical of green algae, with chlorophylls a and b, and lutein as the dominant carotenoid.
    European Journal of Phycology 01/2013; 48(4):427. · 2.34 Impact Factor

Publication Stats

977 Citations
212.37 Total Impact Points

Institutions

  • 2003–2014
    • Eötvös Loránd University
      • Department of Microbiology
      Budapeŝto, Budapest, Hungary
  • 2012
    • Babeş-Bolyai University
      • Faculty of Biology and Geology
      Cluj-Napoca, Judetul Cluj, Romania
  • 2010
    • Sapientia Hungarian University of Transylvania
      • Department of Bioengineering
      Mercurea Ciuc, Harghita, Romania
  • 2008
    • National Institute of Environmental Health, Hungary
      Budapeŝto, Budapest, Hungary
    • Central Agricultural Office
      Budapeŝto, Budapest, Hungary
  • 2007
    • National Institute for Food and Nutrition Science
      Budapeŝto, Budapest, Hungary
  • 2000–2005
    • Szent István University, Godollo
      • • Department of Parasitology and Zoology
      • • Faculty of Veterinary Science
      Gödölö, Pest, Hungary
  • 2004
    • Academy of Sciences of the Czech Republic
      • Ústav půdní biologie
      Praha, Hlavni mesto Praha, Czech Republic