Project description:Phylogenetic, microbiological and comparative genomic analysis was used to examine the diversity among members of the genus Caldicellulosiruptor with an eye towards the capacity of these extremely thermophilic bacteria for degrading the complex carbohydrate content of plant biomass. Seven species from this genus (C. saccharolyticus, C. bescii (formerly Anaerocellum thermophilum), C. hydrothermalis, C. owensensis, C. kronotskyensis, C. lactoaceticus, and C. kristjanssonii) were compared on the basis of 16S rRNA phylogeny and cross-species DNA-DNA hybridization to a whole genome C. saccharolyticus oligonucleotide microarray. Growth physiology of the seven Caldicellulosiruptor species on a range of carbohydrates showed that, while all could be cultivated on acid pre-treated switchgrass, only C. saccharolyticus, C. besci, C. kronotskyensis, and C. lactoaceticus were capable of hydrolyzing Whatman No. 1 filter paper. Two-dimensional gel electrophoresis of the secretomes from cells grown on microcrystalline cellulose revealed that species capable of crystalline cellulose hydrolysis also had diverse secretome fingerprints. The two-dimensional secretome of C. saccharolyticus revealed a prominent S-layer protein that appears to be also indicative of highly cellulolytic Caldicellulosiruptor species, suggesting a possible role in cell-substrate interaction. These growth physiology results were also linked to glycoside hydrolase and carbohydrate-binding module inventories for the seven bacteria, deduced from draft genome sequence information. These preliminary inventories indicated that the absence of a single glycoside hydrolase family and carbohydrate binding motif family appear to be responsible for some Caldicellulosiruptor species’ diminished cellulolytic capabilities. Overall, the genus Caldicellulosiruptor appears to contain more genomic and physiological diversity than previously reported, and is well suited for biomass deconstruction applications.
2010-11-29 | GSE23606 | GEO
Project description:Screening of Fomesafen Degrading Bacteria
| PRJNA589242 | ENA
Project description:Screening of cyproconazole degrading bacteria
Project description:For phytophagous insects, the efficiency of utilization of hemicellulose and cellulose depends on the gut microbiota. Shifts in environmental and management conditions alter the presence and abundance of plant species which may induce adaptations in the diversity of gut microbiota. To test the adaptation of the microbiota to a shift from a natural diverse to a monocultural meadow with Dactylis glomerata the highly abundant grasshopper species, Chorthippus dorsatus, was taken from the wild and kept in captivity and were fed with Dactylis glomerata for five days. The feces were collected and analyzed by metaproteomics. After the diet shift from a diverse source to the single source, the microbiota composition stays relatively stable. The Bacilli as the group of highest abundance did not change on the functional level. In contrast, pronounced shifts of amino acid and carbohydrate metabolism in Clostridia and Proteobacteria were observed. Hence, the adaptation upon short-term change of food source in this grasshopper species is dominated by functional adaptations and not by shifts in the community structure of the microbiota. This suggests that the microbiota of grasshoppers is capable to cope also with the loss of diverse feeding plants at least for a shorter time period.
Project description:Phylogenetic, microbiological and comparative genomic analysis was used to examine the diversity among members of the genus Caldicellulosiruptor with an eye towards the capacity of these extremely thermophilic bacteria for degrading the complex carbohydrate content of plant biomass. Seven species from this genus (C. saccharolyticus, C. bescii (formerly Anaerocellum thermophilum), C. hydrothermalis, C. owensensis, C. kronotskyensis, C. lactoaceticus, and C. kristjanssonii) were compared on the basis of 16S rRNA phylogeny and cross-species DNA-DNA hybridization to a whole genome C. saccharolyticus oligonucleotide microarray. Growth physiology of the seven Caldicellulosiruptor species on a range of carbohydrates showed that, while all could be cultivated on acid pre-treated switchgrass, only C. saccharolyticus, C. besci, C. kronotskyensis, and C. lactoaceticus were capable of hydrolyzing Whatman No. 1 filter paper. Two-dimensional gel electrophoresis of the secretomes from cells grown on microcrystalline cellulose revealed that species capable of crystalline cellulose hydrolysis also had diverse secretome fingerprints. The two-dimensional secretome of C. saccharolyticus revealed a prominent S-layer protein that appears to be also indicative of highly cellulolytic Caldicellulosiruptor species, suggesting a possible role in cell-substrate interaction. These growth physiology results were also linked to glycoside hydrolase and carbohydrate-binding module inventories for the seven bacteria, deduced from draft genome sequence information. These preliminary inventories indicated that the absence of a single glycoside hydrolase family and carbohydrate binding motif family appear to be responsible for some Caldicellulosiruptor species’ diminished cellulolytic capabilities. Overall, the genus Caldicellulosiruptor appears to contain more genomic and physiological diversity than previously reported, and is well suited for biomass deconstruction applications. Six dye-flip experiments were conducted using C. saccharolyticus genomic DNA as the reference in each dye-flip, and one of six different Caldicellulosiruptor spp. as a tester in each dye-flip
Project description:Hyperthermophilic bacteria of the genus Thermotoga are known to utilize a wide range of simple and complex polysaccharides. T. maritima's transcriptional response to a variety of mono- and poly-saccharides was previously studied to assign functions to genes involved in carbohydrate uptake and utilization. To compare and contrast closely-related members of the Thermotoga genus, a four-species microarray was developed by expanding a whole genome T. maritima array to include unique genes from three other species (T. neapolitana, T. petrophila, and T. sp. RQ2). This multi-species array was used to investigate the diversity of the genus, specifically the response of each of the four species to a mixture of polysaccharides (galactomannan, glucomannan, xylan, pectin, lichenan, and carboxymethyl cellulose).
Project description:Evidence shows that bacteria contribute actively to the decomposition of cellulose and hemicellulose in forest soil; however, their role in this process is still unclear. Here we performed the screening and identification of bacteria showing potential cellulolytic activity from litter and organic soil of a temperate oak forest. The genomes of three cellulolytic isolates previously described as abundant in this ecosystem were sequenced and their proteomes were characterized during the growth on plant biomass and on microcrystalline cellulose. Pedobacter and Mucilaginibacter showed complex enzymatic systems containing highly diverse carbohydrate-active enzymes for the degradation of cellulose and hemicellulose, which were functionally redundant for endoglucanases, -glucosidases, endoxylanases, -xylosidases, mannosidases and carbohydrate-binding modules. Luteibacter did not express any glycosyl hydrolases traditionally recognized as cellulases. Instead, cellulose decomposition was likely performed by an expressed GH23 family protein containing a cellulose-binding domain. Interestingly, the presence of plant lignocellulose as well as crystalline cellulose both trigger the production of a wide set of hydrolytic proteins including cellulases, hemicellulases and other glycosyl hydrolases. Our findings highlight the extensive and unexplored structural diversity of enzymatic systems in cellulolytic soil bacteria and indicate the roles of multiple abundant bacterial taxa in the decomposition of cellulose and other plant polysaccharides.