Search

Background: Celastrus angulatus Maxim is a kind of crucial and traditional insecticidal plant widely distributed in the mountains of southwest China. Celangulin V is the efficient insecticidal sesquiterpenoid of C. angulatus and widely used in pest control in China, but the low yield and discontinuous supply impeded its further popularization and application. Fortunately, the development of synthetic biology provided an opportunity for sustainable supply of Celangulin V, for which understanding its biosynthetic pathway is indispensable. Results: In this study, six cDNA libraries were prepared from leaf and root of C. angulatus before global transcriptome analyses using the BGISEQ-500 platform. A total of 104,950 unigenes were finally obtained with an average length of 1200 bp in six transcriptome databases of C. angulatus, in which 51,817 unigenes classified into 25 KOG classifications, 39,866 unigenes categorized into 55 GO functional groups, and 48,810 unigenes assigned to 135 KEGG pathways, 145 of which were putative biosynthetic genes of sesquiterpenoid and triterpenoid. 16 unigenes were speculated to be related to Celangulin V biosynthesis. De novo assembled sequences were verified by Quantitative Real-Time PCR (qRT-PCR) analysis. Conclusions: This study is the first report on transcriptome analysis of C. angulatus, and 16 unigenes probably involved in the biosynthesis of Celangulin V were finally collected. The transcriptome data will make great contributions to research for this specific insecticidal plant and the further gene mining for biosynthesis of Celangulin V and other sesquiterpene polyol esters. [ABSTRACT FROM AUTHOR]

Background: Mucormycosis is a highly lethal fungal infection especially in immunocompromised individuals.Methods: In order to review the epidemiology, diagnosis, and treatment of mucormycosis in renal transplant recipients we searched publications of mucormycosis cases in renal transplant recipients in PUBMED database up to December 2015.Results: A total of 174 cases in renal transplant recipients were included in this review. Most of the cases (76%) were male. Major underlying diseases were diabetes mellitus (43.1%). Rhinocerebral was the most common site of infection (33.3%). Rhizopus species was the most frequent fungus (59.1%) in patients with pathogen identified to species level. The mortality rates of disseminated mucormycosis (76.0%) and graft renal (55.6%) were higher than infection in other sites. The overall survival in patients received surgical debridement combined with amphotericin B/posaconazole (70.2%) was higher than those who received antifungal therapy alone (32.4%), surgery alone (36.4%) or without therapy (0%) (p < 0.001). The overall survivals in patients receiving posaconazole and lipid amphoterincin B were higher than that receiving deoxycholate formulation (92.3% and 73.4% vs 47.4%).Conclusions: Mucormycosis is a severe infection in renal transplant recipients. Surgical debridement combined with antifungals, especially liposomal amphotericin B and posaconazole, can significantly improve patient's overall survival. [ABSTRACT FROM AUTHOR]

Background: Recent studies have demonstrated that photosynthetic cyanobacteria could be an excellent cell factory to produce renewable biofuels and chemicals due to their capability to utilize solar energy and CO2 as the sole energy and carbon sources. Biosynthesis of carbon-neutral biofuel alkanes with good chemical and physical properties has been proposed. However, to make the process economically feasible, one major hurdle to improve the low cell tolerance to alkanes needed to be overcome. Results: Towards the goal to develop robust and high-alkane-tolerant hosts, in this study, the responses of model cyanobacterial Synechocystis PCC 6803 to hexane, a representative of alkane, were investigated using a quantitative proteomics approach with iTRAQ - LC-MS/MS technologies. In total, 1,492 unique proteins were identified, representing about 42% of all predicted protein in the Synechocystis genome. Among all proteins identified, a total of 164 and 77 proteins were found up- and down-regulated, respectively. Functional annotation and KEGG pathway enrichment analyses showed that common stress responses were induced by hexane in Synechocystis. Notably, a large number of transporters and membrane-bound proteins, proteins against oxidative stress and proteins related to sulfur relay system and photosynthesis were induced, suggesting that they are possibly the major protection mechanisms against hexane toxicity. Conclusion: The study provided the first comprehensive view of the complicated molecular mechanism employed by cyanobacterial model species, Synechocystis to defend against hexane stress. The study also provided a list of potential targets to engineer Synechocystis against hexane stress. [ABSTRACT FROM AUTHOR]

Background: Butanol is an important biofuel and chemical. The development of butanol-tolerant strains and the identification of functional butanol-tolerant genes is essential for high-yield bio-butanol production due to the toxicity of butanol. Results: Escherichia coli BW25113 was subjected for the first time to error-prone PCR-based whole-genome shuffling. The resulting mutants BW1847 and BW1857 were found to tolerate 2% (v/v) butanol and short-chain alcohols, including ethanol, isobutanol, and 1-pentanol. The mutants exhibited good stability under butanol stress, indicating that they are potential host strains for the construction of butanol pathways. BW1847 had better butanol tolerance than BW1857 under 0–0.75% (v/v) butanol stress, but showed a lower tolerance than BW1857 under 1.25–2% (v/v) butanol stress. Genome resequencing and PCR confirmation revealed that BW1847 and BW1857 had nine and seven single nucleotide polymorphisms, respectively, and a common 14-kb deletion. Functional complementation experiments of the SNPs and deleted genes demonstrated that the mutations of acrB and rob gene and the deletion of TqsA increased the tolerance of the two mutants to butanol. Genome-wide site-specific mutated strains DT385 (acrB C1198T) and DT900 (rob AT686–7) also showed significant tolerance to butanol and had higher butanol efflux ability than the control, further demonstrating that their mutations yield an inactive protein that enhances butanol resistance characteristics. Conclusions: Stable E. coli mutants with enhanced short alcohols and high concentrations of butanol tolerance were obtained through a rapid and effective method. The key genes of butanol tolerance in the two mutants were identified by comparative functional genomic analysis. [ABSTRACT FROM AUTHOR]

Background: Mucormycosis is a highly lethal fungal infection especially in immunocompromised individuals., Methods: In order to review the epidemiology, diagnosis, and treatment of mucormycosis in renal transplant recipients we searched publications of mucormycosis cases in renal transplant recipients in PUBMED database up to December 2015., Results: A total of 174 cases in renal transplant recipients were included in this review. Most of the cases (76%) were male. Major underlying diseases were diabetes mellitus (43.1%). Rhinocerebral was the most common site of infection (33.3%). Rhizopus species was the most frequent fungus (59.1%) in patients with pathogen identified to species level. The mortality rates of disseminated mucormycosis (76.0%) and graft renal (55.6%) were higher than infection in other sites. The overall survival in patients received surgical debridement combined with amphotericin B/posaconazole (70.2%) was higher than those who received antifungal therapy alone (32.4%), surgery alone (36.4%) or without therapy (0%) (p < 0.001). The overall survivals in patients receiving posaconazole and lipid amphoterincin B were higher than that receiving deoxycholate formulation (92.3% and 73.4% vs 47.4%)., Conclusions: Mucormycosis is a severe infection in renal transplant recipients. Surgical debridement combined with antifungals, especially liposomal amphotericin B and posaconazole, can significantly improve patient's overall survival.

Background: Protein farnesylation is an important tosttranslational modification in fungi. We evaluated the antifungal activity of two farnesyltransferase inhibitors against clinical isolates of Aspergillus and Candida., Methods: Disk diffusion assay and broth microdilution assay were used to determine the antifungal susceptibility of two farnesyltransferase inhibitors (manumycin A and tipifarnib) against clinical isolates of Aspergillus and Candida., Results: Disk diffusion assay demonstrated both agents had activity against Aspergillus and Candida. The minimal inhibitory concentration (MIC) ranges for manumycin A against Aspergillus and Candida were 200 to 400 μM and 13 to >25 μM, respectively. Unfortunately, the MIC were vastly higher than the concentrations that inhibit the proliferation and viability of mammalian cells. The MICs of tipifarnib against Aspergillus and Candida were >1600 μM., Conclusion: The outcome of present study showed that farnesyltransferase inhibitors have activity against Aspergillus and Candida. This suggests that farnesyltransferase may be used as anifungal target in designing and developing new drugs.

Background: Photosynthetic cyanobacteria have been recently proposed as a 'microbial factory' to produce butanol due to their capability to utilize solar energy and CO2 as the sole energy and carbon sources, respectively. However, to improve the productivity, one key issue needed to be addressed is the low tolerance of the photosynthetic hosts to butanol., Results: In this study, we first applied a quantitative transcriptomics approach with a next-generation RNA sequencing technology to identify gene targets relevant to butanol tolerance in a model cyanobacterium Synechocystis sp. PCC 6803. The results showed that 278 genes were induced by the butanol exposure at all three sampling points through the growth time course. Genes encoding heat-shock proteins, oxidative stress related proteins, transporters and proteins involved in common stress responses, were induced by butanol exposure. We then applied GC-MS based metabolomics analysis to determine the metabolic changes associated with the butanol exposure. The results showed that 46 out of 73 chemically classified metabolites were differentially regulated by butanol treatment. Notably, 3-phosphoglycerate, glycine, serine and urea related to general stress responses were elevated in butanol-treated cells. To validate the potential targets, we constructed gene knockout mutants for three selected gene targets. The comparative phenotypic analysis confirmed that these genes were involved in the butanol tolerance., Conclusion: The integrated OMICS analysis provided a comprehensive view of the complicated molecular mechanisms employed by Synechocystis sp. PCC 6803 against butanol stress, and allowed identification of a series of potential gene candidates for tolerance engineering in cyanobacterium Synechocystis sp. PCC 6803.

Background: Fermentation production of biofuel ethanol consumes agricultural crops, which will compete directly with the food supply. As an alternative, photosynthetic cyanobacteria have been proposed as microbial factories to produce ethanol directly from solar energy and CO2. However, the ethanol productivity from photoautotrophic cyanobacteria is still very low, mostly due to the low tolerance of cyanobacterial systems to ethanol stress., Results: To build a foundation necessary to engineer robust ethanol-producing cyanobacterial hosts, in this study we applied a quantitative transcriptomics approach with a next-generation sequencing technology, combined with quantitative reverse-transcript PCR (RT-PCR) analysis, to reveal the global metabolic responses to ethanol in model cyanobacterial Synechocystis sp. PCC 6803. The results showed that ethanol exposure induced genes involved in common stress responses, transporting and cell envelope modification. In addition, the cells can also utilize enhanced polyhydroxyalkanoates (PHA) accumulation and glyoxalase detoxication pathway as means against ethanol stress. The up-regulation of photosynthesis by ethanol was also further confirmed at transcriptional level. Finally, we used gene knockout strains to validate the potential target genes related to ethanol tolerance., Conclusion: RNA-Seq based global transcriptomic analysis provided a comprehensive view of cellular response to ethanol exposure. The analysis provided a list of gene targets for engineering ethanol tolerance in cyanobacterium Synechocystis.

Background: Amyloidosis cutis dyschromica is a rarely documented variant of cutaneous amyloidosis. To date, only 26 cases have been reported., Objective: The purpose of this study was to improve the clinical and histopathological data for this variant of amyloidosis and to highlight the immunohistochemical features of the disease. The published cases were also reviewed., Methods: We performed a retrospective review of patients with amyloidosis cutis dyschromica in a single centre. The clinical, histopathological and immunohistochemical features were documented and analysed., Observations: We described 10 cases of amyloidosis cutis dyschromica. Six of them were female. Five patients were from the same family, and the other 5 were sporadic. The distinguishing features of the clinical presentation included generalised mottled hyper- and hypopigmented macules, which were asymptomatic or mild pruritic. The typical onset of the lesions occurred in childhood (n = 7) and occasionally after puberty (n = 3). No evidence of systemic amyloidosis deposition was observed in these cases of amyloidosis cutis dyschromica. Amyloid deposits were observed in the papillary dermis and were positive for the Congo red stain. An immunohistochemical study showed that the amyloid expresses cytokeratins CK34βE12 and CK5/6., Conclusions: We described the largest series of amyloidosis cutis dyschromica to date and reviewed the published patients. This rare disease is featured by generalised mottled hyper- and hypopigmented lesions, and it is a rare variant of primary cutaneous amyloidosis without evidence of systemic amyloid deposition. Positive staining for the cytokeratins CK34βE12 and CK5/6 in amyloidosis cutis dyschromica suggests that the amyloid is derived from keratinocytes.

Dermatofibrosarcoma protuberans is a locally aggressive mesenchymal neoplasm. It usually presents as an indurated plaque that protrudes above the surface of the skin. Some patients have clinically persistent plaques that might be atrophic. The atrophic variant of dermatofibrosarcoma protuberans may be confused with some common skin diseases with atrophic appearance. We reported a 40-year-old woman who had a 10-year history of an atrophic dermatofibrosarcoma protuberans. Molecular analysis showed a fusion between COL1A1 exon 31 to exon 2 of PDGFB. The lesion was totally excised, with negative margins of the resection demonstrated by CD34 immunostaining. To our knowledge, this is the second case of atrophic dermatofibrosarcoma protuberans confirmed by detection of COL1A1-PDGFB fusion gene. This appears to be the first report of a fusion between COL1A1 exon 31 to exon 2 of PDGFB in atrophic dermatofibrosarcoma protuberans., Virtual Slides: The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1249657688795311.