Project description:Caldicellulosiruptor saccharolyticus is an extremely thermophilic, Gram-positive anaerobe, which ferments cellulose-, hemicellulose- and pectin-containing biomass to acetate, CO2 and hydrogen. Its broad substrate range, high hydrogen-producing capacity, and ability to co-utilize glucose and xylose, make this bacterium an attractive candidate for microbial bioenergy production. Glycolytic pathways and an ABC-type sugar transporter were significantly up-regulated during growth on glucose and xylose, indicating that C. saccharolyticus co-ferments these sugars unimpeded by glucose-based catabolite repression. The capacity to simultaneously process and utilize a range of carbohydrates associated with biomass feedstocks represents a highly desirable feature of a lignocellulose-utilizing, biofuel-producing bacterium. Keywords: substrate response
Project description:Mycorrhiza helper bacteria (MHB) promote the formation of ectomycorrhizae between tree roots and ectomycorrhizal fungi. Despite the high relevance of MHB for forestry and for sustainable tree production in tree nurseries, little is known about the properties of the bacteria that contribute to their helper abilities. The MHB strain Pseudomonas fluorescens BBc6R8 is used as a model to study the mechanisms of the helper effect. We took advantage of new technologies to obtain, for the first time, the whole genome sequence of an MHB. Analyses reveal an important plasticity of the genome with numerous functions acquired by horizontal gene tranfer. Genome mining was combined with transcriptomic and mutagenesis approaches to reveal molecular determinants of the helper effect. The data suggest that the production of helper molecules is likely to be constitutive in vitro. The helper effect appears to be pleiotropic and to rely, for a substantial part, on trophic interactions. Despite its helper abilities, the bacterium is also able in specific conditions to outcompete ectomycorrhizal fungi and inhibit their growth. We conclude that the helper bacterium possess a broad range of properties whose expression depending on the biotic and abiotic conditions can result in either a beneficial, neutral or antagonistic interaction between the plant, the ectomycorrhizal fungus and the bacterium.
Project description:ITALIC! Aeromicrobium erythreumNRRL B-3381 has a 3,629,239-bp circular genome that has 72% G+C content. There are at least 3,121 coding sequences (CDSs), two rRNA gene operons, and 47 tRNAs. The genome and erythromycin ( ITALIC! ery) biosynthetic gene sequences provide resources for metabolic and combinatorial engineering of polyketides.
Project description:We measured abundances of tRNAs by means of hydro-tRNA-seq (Gogakos et al., 2017), a method based on partial alkaline RNA hydrolysis that generates fragments suitable for sequencing, in the genome-reduced bacterium Mycoplasma pneumoniae.
Project description:Given the facilities for whole genome sequencing with next-generation sequencers, structural and functional gene annotation is now only based on automated prediction. However, errors in terms of gene structure are still frequently reported especially for the correct determination of initiation start codons. Here, we propose a strategy to enrich and detect protein N-termini by mass spectrometry in order to refine genome annotation. After selective protein N-termini derivatization using (N-Succinimidyloxycarbonylmethyl)tris(2,4,6-trimethoxyphenyl)phosphonium bromide (TMPPAc-OSu) as labeling reagent, protein digestion was performed with three proteases in parallel. TMPP-labeled N-terminal-most peptides were further resolved from internal peptides by the COmbined FRActional DIagonal Chromatography (COFRADIC) sorting methodology before analysis with tandem mass spectrometry. We refined the annotation of the genome of a model marine bacterium, Roseobacter denitrificans.
