Nejvíce citovaný článek - PubMed ID 11542017
There are two main types of bacterial photosynthesis: oxygenic (cyanobacteria) and anoxygenic (sulfur and non-sulfur phototrophs). Molecular mechanisms of photosynthesis in the phototrophic microorganisms can differ and depend on their location and pigments in the cells. This paper describes bacteria capable of molecular oxidizing hydrogen sulfide, specifically the families Chromatiaceae and Chlorobiaceae, also known as purple and green sulfur bacteria in the process of anoxygenic photosynthesis. Further, it analyzes certain important physiological processes, especially those which are characteristic for these bacterial families. Primarily, the molecular metabolism of sulfur, which oxidizes hydrogen sulfide to elementary molecular sulfur, as well as photosynthetic processes taking place inside of cells are presented. Particular attention is paid to the description of the molecular structure of the photosynthetic apparatus in these two families of phototrophs. Moreover, some of their molecular biotechnological perspectives are discussed.
- Klíčová slova
- anaerobes, anoxygenic bacteria, detoxification, hydrogen sulfide, molecular mechanisms of photosynthesis, water environment,
- MeSH
- anaerobióza MeSH
- Chlorobi klasifikace genetika fyziologie MeSH
- Chromatiaceae klasifikace genetika fyziologie MeSH
- fototrofní procesy genetika MeSH
- fylogeneze MeSH
- síra metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- síra MeSH
Freshwater environments teem with microbes that do not have counterparts in culture collections or genetic data available in genomic repositories. Currently, our apprehension of evolutionary ecology of freshwater bacteria is hampered by the difficulty to establish organism models for the most representative clades. To circumvent the bottlenecks inherent to the cultivation-based techniques, we applied ecogenomics approaches in order to unravel the evolutionary history and the processes that drive genome architecture in hallmark freshwater lineages from the phylum Planctomycetes. The evolutionary history inferences showed that sediment/soil Planctomycetes transitioned to aquatic environments, where they gave rise to new freshwater-specific clades. The most abundant lineage was found to have the most specialised lifestyle (increased regulatory genetic circuits, metabolism tuned for mineralization of proteinaceous sinking aggregates, psychrotrophic behaviour) within the analysed clades and to harbour the smallest freshwater Planctomycetes genomes, highlighting a genomic architecture shaped by niche-directed evolution (through loss of functions and pathways not needed in the newly acquired freshwater niche).
Genetic diversity among 43 petroleum hydrocarbon-degrading Pseudomonas belonging to four different species and the type strain Pseudomonas aeruginosa MTCC1034 was assessed by using restriction fragment length polymorphism (RFLP) of polymerase chain reaction (PCR)-amplified 16S-23S rDNA intergenic spacer regions (ISRs) polymorphism. PCR amplification from all Pseudomonas species yielded almost identical ISR amplicons of "?" 800 bp and in nested PCR of "?" 550 bp. The RFLP analysis with MboI and AluI revealed considerable intraspecific variations within the Pseudomonas species. The dendrogram constructed on the basis of the PCR-RFLP patterns of 16S-23S rDNA intergenic spacer regions differentiated all the species into seven different clusters.
- MeSH
- DNA bakterií genetika MeSH
- fylogeneze MeSH
- mezerníky ribozomální DNA genetika MeSH
- polymerázová řetězová reakce metody MeSH
- polymorfismus délky restrikčních fragmentů * MeSH
- Pseudomonas klasifikace genetika izolace a purifikace metabolismus MeSH
- RNA ribozomální 16S genetika MeSH
- RNA ribozomální 23S genetika MeSH
- ropa mikrobiologie MeSH
- techniky typizace bakterií metody MeSH
- uhlovodíky metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- Názvy látek
- DNA bakterií MeSH
- mezerníky ribozomální DNA MeSH
- RNA ribozomální 16S MeSH
- RNA ribozomální 23S MeSH
- ropa MeSH
- uhlovodíky MeSH
