Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Chromatiaceae”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Polar lipids in phototrophic bacteria of the Rhodospirillaceae and Chromatiaceae families.

The polar lipids of photosynthetic purple bacteria of the genera Chromatium, Thiocapsa, Thiocystis, Ectothiorhodospira, Rhodopseudomonas, Rhodospirillum, and Rhodomicrobium were analyzed. Characteristic compositions of the polar lipids were found for most of the Rhodospirillaceae and Chromatiaceae species. Phosphatidylethanolamine, phosphatidylglycerol, and cardiolipin were the major phospholipids in most species. Phosphatidylcholine was present as a major component in all species of the genus Ectothiorhodospira, but was not detected in the remaining Chromatiaceae. It was also present in most of the Rhodospirillaceae species. No glycolipids were found in any of the Ectothiorhodospira species. In the Rhodospirillaceae, the glycolipids mono- and digalactosyl diglycerides were generally absent. Sulfoquinovosyl diglyceride was present in significant amounts in at least three species of the Rhodospirillaceae and may have been present in most of them, but only in traces. All of the Chromatiaceae species contained several glycolipids, one of which was similar to monogalactosyl diglyceride. Ornithine lipids were found in large amounts in most Rhodospirillaceae, but were absent in Ectothiorhodospira and in the other Chromatiaceae. The species examined could be divided into three groups on the basis of their lipid composition: (i) the genus Ectothiorhodospira; (ii) the remaining Chromatiaceae; and (iii) the Rhodospirillaceae. The data presented are compared with those available in the literature, and differences from other phototrophic organisms are discussed.

Chromatiaceae↗

Phylogenetic relationships among the Chromatiaceae, their taxonomic reclassification and description of the new genera Allochromatium, Halochromatium, Isochromatium, Marichromatium, Thiococcus, Thiohalocapsa and Thermochromatium.

Sequences of the 16S rDNA from all available type strains of Chromatium species have been determined and were compared to those of other Chromatiaceae, a few selected Ectothiorhodospiraceae and Escherichia coli. The clear separation of Ectothiorhodospiraceae and Chromatiaceae is confirmed. Most significantly the sequence comparison revealed a genetic divergence between Chromatium species originated from freshwater sources and those of truly marine and halophilic nature. Major phylogenetic branches of the Chromatiaceae contain (i) marine and halophilic species, (ii) freshwater Chromatium species together with Thiocystis species and (iii) species of the genera Thiocapsa and Amoebobacter as recently reclassified [Guyoneaud, R. & 6 other authors (1988). Int J Syst Bacteriol 48, 957-964], namely Thiocapsa roseopersicina, Thiocapsa pendens (formerly Amoebobacter pendens), Thiocapsa rosea (formerly Amoebobacter roseus), Amoebobacter purpureus and Thiolamprovum pedioforme (formerly Amoebobacter pedioformis). The genetic relationships between the species and groups are not in congruence with the current classification of the Chromatiaceae and a reclassification is proposed on the basis of 16S rDNA sequence similarity supported by selected phenotypic properties. The proposed changes include the transfers of Chromatium minus and Chromatium violascens to Thiocystis minor comb. nov. and Thiocystis violascens comb. nov., of Chromatium vinosum, Chromatium minutissimum and Chromatium warmingii to the new genus Allochromatium as Allochromatium vinosum comb. nov., Allochromatium minutissimum comb. nov., and Allochromatium warmingii comb. nov., of Chromatium tepidum to the new genus Thermochromatium as Thermochromatium tepidum comb. nov., of Chromatium salexigens and Chromatium glycolicum to the new genus Halochromatium as Halochromatium salexigens comb. nov. and Halochromatium glycolicum comb. nov., of Chromatium gracile and Chromatium purpuratum to the new genus as Marichromatium gracile comb. nov. and Marichromatium purpuratum comb. nov., of Thiocapsa pfennigii to Thiococcus pfennigii gen. nom. rev., of Thiocapsa halophila to the new genus Thiohalocapsa as Thiohalocapsa halophila comb. nov., and of Chromatium buderi to the new genus Isochromatium as Isochromatium buderi comb. nov.

Chromatiaceae↗

Lipopolysaccharides of Thiocystis violacea, Thiocapsa pfennigii, and Chromatium tepidum, species of the family Chromatiaceae.

The lipopolysaccharides (LPS) of three species of purple sulfur bacteria (Chromatiaceae), Thiocystis violacea, Thiocapsa pfennigii, and the moderately thermophilic bacterium Chromatium tepidum, were isolated. The LPS of Thiocystis violacea and Chromatium tepidum contained typical O-specific sugars, indicating O-chains. Long O-chains were confirmed for these species by sodium deoxycholate gel electrophoresis of their LPS. Thiocapsa pfennigii, however, had short or no O-chains. The core region of the LPS of all three species comprised D-glycero-D-mannoheptose as the only heptose and 2-keto-3-deoxyoctonate. The lipid A, obtained from the LPS by mild acid hydrolysis, contained glucosamine as the main amino sugar. Amide-bound 3-hydroxymyristic acid was the only hydroxy fatty acid. The main ester-bound fatty acid in all lipid A fractions was 12:0. Mannose and small amounts of 2,3-diamino-2,3-dideoxy-D-glucose were common constituents of the lipid A of the three Chromatiaceae species investigated. All lipid A fractions were essentially free of phosphate.

Chromatiaceae↗

[On the ecology of marine chromatiaceae and chlorobiaceae (author's transl)].

Number and genera (types) of phototrophic red and green sulfur bacteria have been determined in the upper layer of eleven marine sediment samples from the euphotic zone in the Mediterranean Sea. Origin and nature of the sediment samples are given as well as their pH, total nitrogen and sulfide content. The results show that the sediments studied did not provide good growth conditions for Chromatiaceae (Chromatium, Thiocystis, Thiocapsa) and Chlorobiaceae (Prosthecochloris). The total number of these bacteria varied in agreement with the total nitrogen content (organic matter) of the samples; the organic matter content is, therefore, of primary importance for the occurrence of the red and green sulfur bacteria in the samples.

Chromatiaceae↗

Utilization of nitrogen compounds and ammonia assimilation by Chromatiaceae.

Chromatium vinosum strain D, Thiocapsa roseopersicina strain 6311 and Ectothiorhodospira mobilis strain 8112 were grown anaerobically in the light with various single nitrogen sources. When substituted for NH4Cl only glutamine and casamino acids supported good growth of all strains tested. Peptone and urea were utilized by C. vinosum and T. roseopersicina, glutamate, asparagine and nitrate only by C. vinosum. The strains were able to grow with molecular nitrogen; complete inhibition of this growth was observed in the presence of alanine with E. mobilis, and of alanine or asparagine with T. roseopersicina. Glutamate dehydrogenase, requiring either NADH or NADPH, NADH-linked glutamate synthase, and glutamine synthetase were demonstrated in the above organisms grown on NH4Cl.

Amino Acids↗

Analysis of subfossil molecular remains of purple sulfur bacteria in a lake sediment.

Molecular remains of purple sulfur bacteria (Chromatiaceae) were detected in Holocene sediment layers of a meromictic salt lake (Mahoney Lake, British Columbia, Canada). The carotenoid okenone and bacteriophaeophytin a were present in sediments up to 11,000 years old. Okenone is specific for only a few species of Chromatiaceae, including Amoebobacter purpureus, which presently predominates in the chemocline bacterial community of the lake. With a primer set specific for Chromatiaceae in combination with denaturing gradient gel electrophoresis, 16S rRNA gene sequences of four different Chromatiaceae species were retrieved from different depths of the sediment. One of the sequences, which originated from a 9, 100-year-old sample, was 99.2% identical to the 16S rRNA gene sequence of A. purpureus ML1 isolated from the chemocline. Employing primers specific for A. purpureus ML1 and dot blot hybridization of the PCR products, the detection limit for A. purpureus ML1 DNA could be lowered to 0.004% of the total community DNA. With this approach the DNA of the isolate was detected in 7 of 10 sediment layers, indicating that A. purpureus ML1 constituted at least a part of the ancient purple sulfur bacterial community. The concentrations of A. purpureus DNA and okenone in the sediment were not correlated, and the ratio of DNA to okenone was much lower in the subfossil sediment layers (2.7 . 10(-6)) than in intact cells (1.4). This indicates that degradation rates are significantly higher for genomic DNA than for hydrocarbon cell constituents, even under anoxic conditions and at the very high sulfide concentrations present in Mahoney Lake.

Base Sequence↗

Structure and composition of freshwater microbial mats from a sulfur spring ("Font Pudosa", NE Spain).

Different types of microbial mats developing on the wall on a non-thermal sulfur freshwater spring have been studied. Both, light and electron microscopy as well as HPLC analysis of photosynthetic pigments revealed their structure and composition. Prokaryotic chlorophylls and carotenoids helped in the taxonomical assignment of the main photosynthetic groups. "Inverted position" mats (Mat-I) were dominated by Chromatiaceae; they were located closed to the water outlets (0.3 mM sulfide). "Normal position", that is, cyanobacterial-covered mats (Mat-II and Mat-IV), developed elsewhere on the stone walls at lower sulfide concentrations. A third type of mat (Mat-III), covered by chemolithotrophic bacteria, was distinguishable at the water-air interface, strongly attached to the walls of the spring. Up to six physiological types of microorganisms have been recognized: cyanobacteria, Chromatiaceae, purple nonsulfur bacteria. Chlorobiaceae, Chloroflexaceae, and chemolithotrophic bacteria. Cyanobacteria Lyngbya-like, Oscillatoria-like and Pseudanabaena sp. were found. The diversity of Chromatiaceae (six morpho-/pigment types of the genus Chromatium, plus two non identified Chromatiaceae, named PB1 and PB2 were observed) was noticeable. Chemolithotrophic bacteria were represented by the genera Beggiatoa and Thiothrix. Finally, small numbers of Chloroflexus-like bacteria and Chlorobium limicola were found in all the studied mats.

Carotenoids↗

A new purple sulfur bacterium isolated from a littoral microbial mat, Thiorhodococcus drewsii sp. nov.

A new strain of purple sulfur bacterium was isolated from a marine microbial mat sampled in Great Sippewissett Salt Marsh at the Atlantic coast (Woods Hole, Mass., USA). Single cells of strain AZ1 were coccus-shaped, highly motile by means of a single flagellum, and did not contain gas vesicles. Intracellular membranes were of the vesicular type. However, additional concentric membrane structures were present. The photosynthetic pigments were bacteriochlorophyll a and carotenoids of the normal spirilloxanthin series, with rhodopin as the dominant carotenoid. Hydrogen sulfide (up to 11 mM), sulfur, thiosulfate, and molecular hydrogen were used as electron donors during anaerobic phototrophic growth. During growth on sulfide, elemental sulfur globules were transiently stored inside the cells. Strain AZ1 is much more versatile than most other Chromatiaceae with respect to electron donor and organic substrates. In the presence of CO(2), it is capable of assimilating C(1)-C(5) fatty acids, alcohols, and intermediates of the tricarboxylic acid cycle. Strain AZ1 could also grow photoorganotrophically with acetate as the sole photosynthetic electron donor. Chemotrophic growth in the dark under microoxic conditions was not detected. Optimum growth occurred at pH 6.5-6.7, 30-35 degrees C, > or =50 micro mol quanta m(-2) s(-1), and 2.4-2.6% NaCl. The DNA base composition was 64.5 mol% G+C. Comparative sequence analysis of the 16S rRNA gene confirmed that the isolate is a member of the family Chromatiaceae. Sequence similarity to the most closely related species, Thiorhodococcus minor DSMZ 11518(T), was 97.8%; however, the value for DNA-DNA hybridization between both strains was only 20%. Because of the low genetic similarity and since strain AZ1 physiologically differs considerably from all other members of the Chromatiaceae, including Trc. minor, the new isolate is described as a new species of the genus Thiorhodococcus, Thiorhodococcus drewsii sp. nov.

Adaptation, Physiological↗

Seasonal and spatial community dynamics in the meromictic Lake Cadagno.

The seasonal and spatial variations in the community structure of bacterioplankton in the meromictic alpine Lake Cadagno were examined by temporal temperature gradient gel electrophoresis (TTGE) of PCR-amplified 16S rDNA fragments. Two different amplifications were performed, one specific for the domain Bacteria (Escherichia coli positions 8-536) and another specific for the family Chromatiaceae (E. coli positions 8-1005). The latter was followed by semi-nested reamplification with the bacterial primer set, allowing comparison of the two PCR approaches by TTGE. The TTGE patterns of samples from the chemocline and the anoxic monimolimnion were essentially identical, whereas the oxic mixolimnion displayed distinctively different banding patterns. For samples from the chemocline and the monimolimnion, dominant bands in the Bacteria-specific TTGE profiles comigrated with bands obtained by the semi-nested PCR approach specific for Chromatiaceae. This observation suggested that Chromatiaceae are in high abundance in the anoxic water layer. All dominant bands were excised and sequenced. Changes in the community structure, as indicated by changes in the TTGE profiles, were observed in samples taken at different times of the year. In the chemocline, Chomatium okenii was dominant in the summer months, whereas Amoebobacter purpureus populations dominated in autumn and winter. This change was confirmed by fluorescent in situ hybridization.

Bacteria↗

Specific detection of different phylogenetic groups of chemocline bacteria based on PCR and denaturing gradient gel electrophoresis of 16S rRNA gene fragments.

Specific amplification of 16S rRNA gene fragments in combination with denaturing gradient gel electrophoresis (DGGE) was used to generate fingerprints of Chromatiaceae, green sulfur bacteria, Desulfovibrionaceae, and beta-Proteobacteria. Sequencing of the gene fragments confirmed that each primer pair was highly specific for the respective phylogenetic group. Applying the new primer sets, the bacterial diversity in the chemoclines of a eutrophic freshwater lake, a saline meromictic lake, and a laminated marine sediment was investigated. Compared to a conventional bacterial primer pair, a higher number of discrete DGGE bands was generated using our specific primer pairs. With one exception, all 15 bands tested yielded reliable 16S rRNA gene sequences. The highest diversity was found within the chemocline microbial community of the eutrophic freshwater lake. Sequence comparison revealed that the six sequences of Chromatiaceae and green sulfur bacteria detected in this habitat all represent distinct and previously unknown phylotypes. The lowest diversity of phylotypes was detected in the chemocline of the meromictic saline lake, which yielded only one sequence each of the Chromatiaceae, beta-2-Proteobacteria, and Desulfovibrionaceae, and no sequences of green sulfur bacteria. The newly developed primer sets are useful for the detection of previously unknown phylotypes, for the comparison of the microbial diversity between different natural habitats, and especially for the rapid monitoring of enrichments of unknown bacterial species.

Bacteria↗

Thiorhodococcus minus, gen. nov., sp. nov., A new purple sulfur bacterium isolated from coastal lagoon sediments.

A new marine phototrophic purple sulfur bacterium (strain CE2203) was isolated in pure culture from a man-made coastal lagoon located on the Atlantic coast (Arcachon Bay, France). Single cells were coccus-shaped, did not contain gas vesicles, and were highly motile. Intracellular photosynthetic membranes were of the vesicular type. Bacteriochlorophyll a and carotenoids of the normal spirilloxanthin series were present as photosynthetic pigments. Hydrogen sulfide, thiosulfate, elemental sulfur, and molecular hydrogen were used as electron donors during photolithotrophic growth under anoxic conditions, while carbon dioxide was utilized as carbon source. Acetate, propionate, lactate, glycolate, pyruvate, fumarate, succinate, fructose, sucrose, ethanol, and propanol were photoassimilated in the presence of hydrogen sulfide. During growth on sulfide, elemental sulfur globules were stored inside the cells. Chemotrophic growth under microoxic conditions in the dark was possible. The DNA base composition was 66.9 mol% G+C. Comparative sequence analysis of the 16S rRNA gene confirmed the membership of strain CE2203 in the family Chromatiaceae. Morphological characteristics of strain CE2203 indicated a close affiliation to the genera Thiocystis and Thiocapsa. However, the phylogenetic treeing revealed no closer relationship to Thiocystis spp. than to Thiocapsa roseopersicina or other known members of the Chromatiaceae. Consequently, strain CE2203 is proposed as the type strain of a new genus and species, Thiorhodococcus minus gen. nov., sp. nov.

Bacteriological Techniques↗

True marine and halophilic anoxygenic phototrophic bacteria.

Anoxygenic phototrophic bacteria are widely distributed in marine sediments and shallow waters of the coastal zone, where they often form intensely colored mass developments. The phototrophic bacteria have adapted to the whole spectrum of salt concentrations, from freshwater to saturated brines, and it is apparent that individual species have adapted well to particular habitats and mineral salts compositions, both qualitatively and quantitatively. This adaptation is reflected not only in the demand for defined ranges of salt concentrations, but also in the phylogenetic relationships of these bacteria, as established by 16S rDNA sequences. Major phylogenetic branches of purple sulfur bacteria are represented by: (1) marine and extremely halophilic Ectothiorhodospiraceae, (2) truly marine and halophilic Chromatiaceae and (3) freshwater Chromatiaceae, some of which are tolerant to low salt concentrations and are successful competitors in brackish and marine habitats. Quite similarly, salt-dependent green sulfur bacteria form distinct phylogenetic lines. In addition, also among the phototrophic alpha-Proteobacteria (purple nonsulfur bacteria), distinct phylogenetic lines of salt-dependent species are recognized. Available data give rise to the assumption that salt concentrations of natural habitats are an important selective factor that determines the development of a selected range of phototrophic bacteria in an exclusive way. As a consequence, the salt responses of these bacteria are reflected in their phylogenetic relationships.

Aerobiosis↗

Taxonomic rearrangements of the genera Thiocapsa and Amoebobacter on the basis of 16S rDNA sequence analyses, and description of Thiolamprovum gen. nov.

Complete nucleotide sequences of the 16S rDNAs were determined from Thiocapsa and Amoebobacter species, including all available type strains and some additional isolates. The distance-matrix analysis and the dendrogram for estimating the genetic relationships revealed that the investigated strains were found in two major clusters within the Chromatiaceae. One cluster comprises all Amoebobacter species, Thiocapsa roseopersicina and several isolates related to Thiocapsa roseopersicina. Representatives of the species Amoebobacter roseus, Amoebobacter pendens and Thiocapsa roseopersicina, the so called 'Thiocapsa roseopersicina group', are very closely related, justifying their inclusion into one genus, Thiocapsa, for which an emended description is presented. Amoebobacter purpureus and Amoebobacter pedioformis formed two separate lines of descent with less than 93% (89.6-92.9%) similarity to strains of the 'Thiocapsa roseopersicina group'. Therefore, they will be considered as two separate genera. As a consequence, an emended description is presented for the genus Amoebobacter, with Amoebobacter purpureus as the new type species and A. pedioformis is transferred to Thiolamprovum pedioforme gen. nov., comb. nov. Two species, Thiocapsa pfennigii and Thiocapsa halophila, which have been classified with the genus Thiocapsa because of their morphological properties, were found within another major cluster of the Chromatiaceae and are only distantly phylogenetically related to the first cluster with 88.4-90.6% and 90.4-92.2% sequence similarity, respectively.

Chromatiaceae↗

[Effect of sunlight penetration on the development of phototrophic sulfur bacteria in marine environment].

Bottles of medium were inoculated with both strains of Chromatiacea and Chlorobiaceae (mixed cultures) and immersed at differnt depths in the marine coastal waters of the Marseilles basin (France). After development, the in vivo absorption characteristics of the cells show the effect of the daylight penetration on the selective growth of photorophic sulfur bacteria. With depth, sunlight selects Chlorobiaceae rich in brown carotenoid pigments to the detriment of Chromatiaceae.

Bacteria↗

Amino acid sequences of two high-potential iron sulfur proteins (HiPIPs) from the moderately halophilic purple phototrophic bacterium Ectothiorhodospira vacuolata.

There are two equally abundant high-potential iron sulfur protein (HiPIP) isozymes present in the purple sulfur bacterium Ectothiorhodospira vacuolata. We have determined the amino acid sequences, which contain 71 and 72 residues. The two HiPIPs can be aligned without any internal insertions or deletions and are 65% identical to one another. The E. vacuolata HiPIPs are most similar to the HiPIP isozymes from Ectothiorhodospira halophila (32-36% identity) and require at least one internal gap for alignment. Other HiPIPs require greater numbers of insertions and deletions for alignment with those of E. vacuolata and E. halophila, and the percentage similarities are slightly smaller (19-40% identity). The E. vacuolata HiPIP isozymes appear to be slightly closer to other species than are the E. halophila isozymes. The E. vacuolata and E. halophila HiPIPs also show slightly greater similarity to the five species of Chromatiaceae, which have been studied, and less similarity to the non-sulfur purple species. These results are in agreement with other studies, which indicate that the two purple sulfur bacterial families, Ectothiorhodospiraceae and Chromatiaceae, are more closely related to one another than to the Rhodospirillaceae.

Amino Acid Sequence↗

Comparison of bacterial populations and chemical composition of dairy wastewater held in circulated and stagnant lagoons.

AIMS: This study compared the chemical, physical and bacterial composition of circulated and stagnant dairy wastewaters. METHODS AND RESULTS: Samples taken from circulated and stagnant wastewater lagoons, over a 1-year period, were analysed for 10 chemical (total N, NH3, NO3, NO2, Na, Ca, HCO3, Fe, P and K) and six physical (biological oxygen demand, chemical oxygen demand, dissolved solids, electrical conductivity, pH and sodium absorption ratio) parameters and were found to be similar. The 16S rDNA genes from the samples were amplified, cloned and BLAST analysed. In total, 996 stagnant and 1052 circulated wastewater derived sequences were obtained, comprising 294 and 362 operational taxonomic units (OTUs) from the circulated and stagnant wastewaters respectively. Coverage estimates of the OTUs identified were 72.1% for the stagnant, and 63.6% for the circulated wastewater libraries. The greatest difference between the two wastewaters was a c. sixfold greater number of sequences representative of the family Chromatiaceae in the circulated wastewater derived library and a c. fivefold greater number of sequences representative of the phylum Chloroflexi in the stagnant wastewater derived library. CONCLUSIONS: Circulation of dairy wastewater does not affect any of the chemical or physical parameters tested; however, circulation does alter the bacterial community structure. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides evidence that circulation of dairy wastewater promotes the growth of bacteria within the family Chromatiaceae and that stagnant systems promote the growth of the phylum Chloroflexi.

Absorption↗

The puf operon of the purple sulfur bacterium Amoebobacter purpureus: structure, transcription and phylogenetic analysis.

The puf operon, encoding photosynthetic reaction center and light-harvesting genes, of the purple sulfur phototrophic bacterium Amoebobacter purpureus was cloned and sequenced. This revealed an unusual operon structure of the genes pufB1 A1 LMCB2 A2 B3 A3. The sequence represents the second complete puf operon available for Chromatiaceae. So far, additional sets of light-harvesting 1 (LH1) genes, pufB2 A2 and pufB3 A3 in the region downstream of pufC have only been described for Allochromatium vinosum. Along with reports of multiple LH1 polypeptides found in some Ectothiorhodospiraceae by direct protein sequencing, our results indicate that multiple LH1 genes may occur frequently in phototrophic gamma-proteobacteria. Phylogenetic analyses suggested a coevolution of the core puf genes pufB1 A1 LM. Separate analysis of the LH1 alpha and beta polypeptides revealed a high intraspecies relatedness for the secondary LH1beta polypeptides, possibly caused by functional constraints. In contrast, LH1alpha subunits of Amb. purpureus and Alc. vinosum are closely related (85% sequence identity) which could reflect horizontal gene transfer. RNA analyses suggested co-transcription of all puf genes in Amb. purpureus as a 5.5 kb primary transcript which appears to be more stable than the puf operon primary transcripts of purple non-sulfur bacteria. The 5' end of the transcript mapped to a putative promoter, which contains a -35 region located in an inverted repeat DNA sequence.

Amino Acid Sequence↗