Project description:Cellulosimicrobium funkei is a rare, opportunistic pathogen. We describe a case of bacteremia and possibly prosthetic valve endocarditis by this organism in a nonimmunocompromised patient. Useful phenotypic tests for differentiating C. funkei from Cellulosimicrobium cellulans and Cellulosimicrobium terreum include motility, raffinose fermentation, glycogen, D-xylose, and methyl-?-D-glucopyranoside assimilation, and growth at 35°C.
Project description:Three rare triterpenoids, saponaceolides Q-S (1-3), have been isolated from fruiting bodies of the mushroom Tricholoma terreum. Their structures were characterized based on extensive spectroscopic data. Compound 1 showed certain cytotoxicities against four human tumor cell lines.
Project description:The symbiosis between ectomycorrhizal fungi and trees is an essential part of forest ecology and depends entirely on the communication between the two partners for establishing and maintaining the relationship. The identification and characterization of differentially expressed genes is a step to identifying such signals and to understanding the regulation of this process. We determined the role of hydrophobins produced by Tricholoma terreum in mycorrhiza formation and hyphal development. A hydrophobin was purified from culture supernatant, and the corresponding gene was identified. The gene is expressed in aerial mycelium and in mycorrhiza. By using a heterologous antiserum directed against a hydrophobin found in the aerial mycelium of Schizophyllum commune, we detected a hydrophobin in the symbiosis between T. terreum and its native pine host Pinus sylvestris. The hydrophobin was found in aerial mycelium of the hyphal mantle and also in the Hartig net hyphae, which form the interface between both partners. Interestingly, this was not the case in the interaction of T. terreum with a host of low compatibility, the spruce Picea abies. The differential expression with respect to host was verified at the transcriptional level by competitive PCR. The differential protein accumulation pattern with respect to host compatibility seen by immunofluorescence staining can thus be attributed at least in part to transcriptional control of the hyd1 gene.
Project description:Despite having serious clinical manifestations, Cellulosimicrobium cellulans remain under-reported with only three genome sequences available at the time of writing. Genome sequences of C. cellulans LMG16121, C. cellulans J36 and Cellulosimicrobium sp. strain MM were used to determine distribution of pathogenicity islands (PAIs) across C. cellulans, which revealed 49 potential marker genes with known association to human infections, e.g. Fic and VbhA toxin-antitoxin system. Oligonucleotide composition-based analysis of orthologous proteins (n?=?791) across three genomes revealed significant negative correlation (P?<?0.05) between frequency of optimal codons (Fopt) and gene G+C content, highlighting the G+C-biased gene conversion (gBGC) effect across Cellulosimicrobium strains. Bayesian molecular-clock analysis performed on three virulent PAI proteins (Fic; D-alanyl-D-alanine-carboxypeptidase; transposase) dated the divergence event at 300?million years ago from the most common recent ancestor. Synteny-based annotation of hypothetical proteins highlighted gene transfers from non-pathogenic bacteria as a key factor in the evolution of PAIs. Additonally, deciphering the metagenomic islands using strain MM's genome with environmental data from the site of isolation (hot-spring biofilm) revealed (an)aerobic respiration as population segregation factor across the in situ cohorts. Using reference genomes and metagenomic data, our results highlight the emergence and evolution of PAIs in the genus Cellulosimicrobium.
Project description:Introduction:Invasive infections due to Cellulosimicrobium spp. (a Gram-positive coryneform) are extremely rare. Only a few cases of bloodstream infections and endocarditis have been described, as bacteraemia due to coryneforms is usually discarded as blood culture contamination. Case presentation:A 66-year-old female, with a history of aortic valve replacement, presented with fever, left leg purpura and acute kidney injury. Multiple repeated blood cultures were positive for Cellulosimicrobium cellulans , and targeted therapy was started. At first, endocarditis was excluded by echocardiograms, and the acute nephritis was interpreted as an atypical presentation of Henoch-Shönlein purpura. High-dose prednisone was started, and after 10 weeks the patient presented again with fever, mental confusion and acute left arm ischaemia. A subsequent echocardiogram and radiolabelled leukocyte scintigraphic evaluation revealed aortic prosthetic valve endocarditis with periprosthetic abscess and arterial brachial thrombosis. The patient deceased, and the autoptic examination confirmed an aortic valve periprosthetic abscess and revealed multiple arterial thromboses and septic embolisms in the kidneys, brain, spleen and myocardium. Conclusion:Isolation of coryneform bacteria on blood culture should not always be discarded as blood culture contamination. In the case of endocarditis due to Cellulosimicrobium spp., the removal of any prosthetic material, along with prolonged in vitro active antimicrobial therapy, should be pursued in order to reduce persistence or relapses of infection.
Project description:A new ganglioside transformed strain isolated from soil was identified as Cellulosimicrobium sp. 21. It produced a sialidase which transformed polysialo-gangliosides GD1 and GT1 into a monosialoterahexosylganglioside, i.e., ganglioside GM1. The sialidase had both NeuAc-?-2,3- and NeuAc-?-2,8-sialidase activity without producing asiolo-GM1. The optimum conditions were evaluated and it was found that the transformation was optimally performed at 30 °C and pH 7.0. The substrate should be added at the beginning of the reaction and the concentration of substrate was 3% (w/v). Under these optimum conditions, Cellulosimicrobium sp. 21 converted GD1 and GT1 into GM1 in inorganic medium in a 5 L bioreactor with the recovery rate of 69.3%. The product contained 50.3% GM1 and was purified on silica to give the product with 95% of GM1 with a recovery rate of 30.5%. Therefore, Cellulosimicrobium sp. 21 has potential to be applied in the production of GM1 in the pharmaceutical industry.