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1.
Shuanghong Zhang Dingyu Liu Zhitao Mao Yufeng Mao Hongwu Ma Tao Chen Xueming Zhao Zhiwen Wang 《Biotechnology letters》2018,40(5):819-827
Objective
To develop an efficient synthetic promoter library for fine-tuned expression of target genes in Corynebacterium glutamicum.Results
A synthetic promoter library for C. glutamicum was developed based on conserved sequences of the ??10 and ??35 regions. The synthetic promoter library covered a wide range of strengths, ranging from 1 to 193% of the tac promoter. 68 promoters were selected and sequenced for correlation analysis between promoter sequence and strength with a statistical model. A new promoter library was further reconstructed with improved promoter strength and coverage based on the results of correlation analysis. Tandem promoter P70 was finally constructed with increased strength by 121% over the tac promoter. The promoter library developed in this study showed a great potential for applications in metabolic engineering and synthetic biology for the optimization of metabolic networks.Conclusions
To the best of our knowledge, this is the first reconstruction of synthetic promoter library based on statistical analysis of C. glutamicum.2.
Korey J. Brownstein Mahmoud Gargouri William R. Folk David R. Gang 《Metabolomics : Official journal of the Metabolomic Society》2017,13(11):133
Introduction
Botanicals containing iridoid and phenylethanoid/phenylpropanoid glycosides are used worldwide for the treatment of inflammatory musculoskeletal conditions that are primary causes of human years lived with disability, such as arthritis and lower back pain.Objectives
We report the analysis of candidate anti-inflammatory metabolites of several endemic Scrophularia species and Verbascum thapsus used medicinally by peoples of North America.Methods
Leaves, stems, and roots were analyzed by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) and partial least squares-discriminant analysis (PLS-DA) was performed in MetaboAnalyst 3.0 after processing the datasets in Progenesis QI.Results
Comparison of the datasets revealed significant and differential accumulation of iridoid and phenylethanoid/phenylpropanoid glycosides in the tissues of the endemic Scrophularia species and Verbascum thapsus.Conclusions
Our investigation identified several species of pharmacological interest as good sources for harpagoside and other important anti-inflammatory metabolites.3.
4.
Yibin Zhuang Jingjie Jiang Huiping Bi Hua Yin Shaowei Liu Tao Liu 《Biotechnology letters》2016,38(4):619-627
Objectives
To produce rosmarinic acid analogues in the recombinant Escherichia coli BLRA1, harboring a 4-coumarate: CoA ligase from Arabidopsis thaliana (At4CL) and a rosmarinic acid synthase from Coleus blumei (CbRAS).Results
Incubation of the recombinant E. coli strain BLRA1 with exogenously supplied phenyllactic acid (PL) and analogues as acceptor substrates, and coumaric acid and analogues as donor substrates led to production of 18 compounds, including 13 unnatural RA analogues.Conclusion
This work demonstrates the viability of synthesizing a broad range of rosmarinic acid analogues in E. coli, and sheds new light on the substrate specificity of CbRAS.5.
Chih-Yueh Liu Chang-Ching Weng Chih-Hsiang Lin Chiou-Ying Yang Kwok-Kong Tony Mong Yaw-Kuen Li 《Biotechnology letters》2017,39(3):407-413
Objectives
A Neissaria bacterial pilus sugar, bacillosamine, was synthesized and, for the first time, used as a probe to screen a single-chain variable fragment (scFv).Results
Four Neisseria, Neisseria gonorrhoeae, Neisseria meningitidis, Neisseria sicca and Neisseria subflava, and two negative controls, Streptococcus pneumoniae and Escherichia coli, were tested through ELISA, immunostaining and gold nanoparticle immunological assay. All results indicated that the selected scFv is feasible for the specific detection of Neisseria species via the recognition of bacillosamine.Conclusions
The recombinant scFv could detect Neisseria strains at 106 CFU/ml.6.
Thais Freitas da Silva Renata Estebanez Vollú Joana Montezano Marques Joana Falcão Salles Lucy Seldin 《Plant and Soil》2017,414(1-2):69-79
Background
The fungus Colletotrichum is a plant pathogen that causes the anthracnose disease, resulting in huge losses in various crops including the rose-scented geranium (Pelargonium graveolens). Although the bacterial community associated with plants has an important role in the establishment of plant diseases, little is known about what happens in P. graveolens.Aims
To increase the knowledge about the bacterial community associated with P. graveolens and its relationship with anthracnose disease symptoms.Methods
Quantitative PCR and high-throughput sequencing were combined to determine the presence of the fungus Colletotrichum and to reveal the bacterial communities associated with different plant parts – root, stem and leaf – and in the rhizosphere and bulk soil, and also to determine the respective bacterial communities associated with P. graveolens leaves symptomatic and asymptomatic for anthracnose disease.Results
The fungus Colletotrichum was detected in all plant parts and in the surrounding soil. Bacterial communities varied spatially in plants, and the disease symptoms also influenced the composition of the bacterial community. Abundances of operational taxonomic units (OTUs) assigned to the phylum Actinobacteria and to the genus Streptococcus were greatly increased in asymptomatic leaves.Conclusions
The bacterial community associated to geranium leaves responds to anthracnose symptoms.7.
Introduction
Cellulose microfibril is a major cell wall polymer that plays an important role in the growth and development of plants. The gene cellulose synthase A (CesA), encoding cellulose synthases, is involved in the synthesis of cellulose microfibrils. However, the regulatory mechanism of CesA gene expression is not well understood, especially during the early developmental stages.Objective
To identify factor(s) that regulate the expression of CesA genes and ultimately control seedling growth and development.Methods
The presence of cis-elements in the promoter region of the eight CesA genes identified in flax (Linum usitatissimum L. ‘Nike’) seedlings was verified, and three kinds of ethylene-responsive cis-elements were identified in the promoters. Therefore, the effect of ethylene on the expression of four selected CesA genes classified into Clades 1 and 6 after treatment with 10?4 and 10?3 M 1-aminocyclopropane-1-carboxylic acid (ACC) was examined in the hypocotyl of 4–6-day-old flax seedlings.Results
ACC-induced ethylene either up- or down-regulated the expression of the CesA genes depending on the clade to which these genes belonged, age of seedlings, part of the hypocotyl, and concentration of ACC.Conclusion
Ethylene might be one of the factors regulating the expression of CesA genes in flax seedlings.8.
Margarita Stritzler Ana Diez Tissera Gabriela Soto Nicolás Ayub 《Biotechnology letters》2018,40(9-10):1419-1423
Objectives
Identification of novel microbial factors contributing to plant protection against abiotic stress.Results
The genome of plant growth-promoting bacterium Pseudomonas fluorescens FR1 contains a short mobile element encoding a novel type of extracellular polyhydroxybutyrate (PHB) polymerase (PhbC) associated with a type I secretion system. Genetic analysis using a phbC mutant strain and plants showed that this novel extracellular enzyme is related to the PHB production in planta and suggests that PHB could be a beneficial microbial compound synthesized during plant adaptation to cold stress.Conclusion
Extracellular PhbC can be used as a new tool for improve crop production under abiotic stress.9.
BACKGROUND
Microbes affect the growth of plants. In this study, the diversity and plant growth-supporting activities of wheat rhizospheric bacteria were examined.METHODS
Sampling was performed thrice at different phases of plant growth. Microbes associated with the rhizoplane of three wheat varieties (Seher, Lasani, and Faisalabad) were cultured and assessed for their plant growth-promoting abilities based on auxin production, hydrogen cyanide production, phosphate solubilization, and nitrogen fixation.RESULTS
Bacterial load (CFU/mL) declined, and the succession of bacterial diversity occurred as the plants aged. Most auxin-producing bacteria and the highest concentrations of auxin (77 μg/mL) were observed during the second sampling point at the tillering stage. The Seher variety harbored the most auxin-producing as well as phosphate-solubilizing bacteria. Most of the bacteria belonged to Bacillus and Pseudomonas. Planomicrobium, Serratia, Rhizobium, Brevundimonas, Stenotrophomonas, and Exiguobacterium sp. were also found.CONCLUSION
These results suggest that the rhizoplane microbiota associated with higher-yield plant varieties have better plant growth-promoting abilities as compared to the microbiota associated with lower-yield plant varieties.10.
Marie GB Hansen Mette Christoffersen Line R Thuesen Morten R Petersen Anders M Bojesen 《Acta veterinaria Scandinavica》2010,52(1):3
Background
Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum are able to infect horses. However, the extend to which Danish horses are infected and seroconvert due to these two bacteria is unknown. The aim of the present study was to evaluate the seroprevalence of B. burgdorferi sensu lato and A. phagocytophilum in Danish horses.Methods
A total of 390 blood samples collected from all major regions of Denmark and with a geographical distribution corresponding to the density of the Danish horse population were analyzed. All samples were examined for the presence of antibodies against B. burgdorferi sensu lato and A. phagocytophilum by the use of the SNAP®4DX ® ELISA test.Results
Overall, 29.0% of the horses were seropositive for B. burgdorferi sensu lato whereas 22.3% were seropositive for A. phagocytophilum.Conclusions
Antibodies against B burgdorferi sensu lato and A. phagocytophilum are commonly found among Danish horses thus showing that Danish horses are frequently infected by these organisms.11.
Pei Han Yong Huang Yumin Xie Wu Yang Wenying Xiang Peter J. Hylands Cristina Legido-Quigley 《Metabolomics : Official journal of the Metabolomic Society》2018,14(7):91
Introduction
In spite of advances in antibiotics, urinary tract infection (UTI) is still among the most common reasons for antibiotic medication worldwide. Persicaria capitata (Buch.-Ham. ex D. Don) H.Gross (P. capitata) is a herbal medicine used by the Miao people in China to treat UTI. However studies of its mechanism are challenging, owing to the complexity of P. capitata with multiple constituents acting on multiple metabolic pathways.Objective
The objective of this study was to explore the working mechanism of P. capitata on urinary tract infection.Methods
Relinqing® granule, which is solely made from aqueous extracts of the whole P. capitata plant, was used in this study. Urine metabolomics based on gas chromatography-mass spectroscopy was employed to assess the metabolic changes caused by administration of Relinqing® granule in a UTI mouse model. Female specific-pathogen-free Kunming mice were divided into control group (mock infection, saline treatment), model group (E.coli infection, saline treatment), Relinqing® group (E.coli infection, Relinqing® granule treatment), ciprofloxacin group (E.coli infection, ciprofloxacin treatment), and sham-Relinqing® group (no surgery, Relinqing® granule treatment).Results
The results showed that after the treatments, urine levels of itaconic acid in Relinqing® group increased by 4.9 fold and 11.3 fold compared with model and ciprofloxacin groups respectively. Itaconic acid is an endogenous antibacterial metabolite produced by macrophages, which also functions as a checkpoint for metabolic reprogramming of macrophage.Conclusion
Our findings suggest that this herbal medicine can cure urinary tract infection through modulation of immune system.12.
Lili Wei Leixi Cao Yanyan Miao Shuju Wu Shumei Xu Ruisheng Wang Jun Du Aihua Liang Yuejun Fu 《Biotechnology letters》2017,39(8):1129-1139
13.
14.
Roman S. Popov Natalia V. Ivanchina Alla A. Kicha Timofey V. Malyarenko Boris B. Grebnev Pavel S. Dmitrenok Valentin A. Stonik 《Metabolomics : Official journal of the Metabolomic Society》2016,12(6):106
Introduction
Starfish are recognized as interesting source of natural steroid products with pharmaceutical potential. Polar steroid metabolites of starfish have unique chemical structures and exhibit various biological activities but their biological functions are controversial.Objectives
The objective of this study was to investigate the response of polar steroid metabolome of the starfish Patiria (=Asterina) pectinifera on various environmental factors and stresses.Methods
Here we first have applied MS-based environmental metabolomics to elucidate the metabolic changes of polar steroid metabolome of starfish. Using HPLC–ESI–Q/TOF–MS approach followed by statistical analysis including principal component analysis and partial least squares discriminant analysis for data classification and potential biomarkers selection, we investigated the changes induced by feeding, injury, variations in water temperature and salinity, and oxygen deficiency.Results
According to multivariate and univariate statistical analysis the responses to feeding, injury and water heating were better expressed than the others and have some similarity in their action on the steroid metabolome of the starfish P. pectinifera. Most constituents of asterosaponin pool were reduced and most constituents of polyhydroxysteroid and related glycoside pool were increased at that.Conclusion
Our results indicate that various metabolic changes in polar steroid constituents of P. pectinifera are induced by feeding and stresses. We believe that these responses are connected with biological multifunctionality of these compounds.15.
Xiaohong Chen Junjun Chen Yuanxing Zhang Ping Zhu Yong Deng Qin Liu 《Biotechnology letters》2016,38(6):959-967
Objective
To achieve secreted expression of the truncated capsid protein from porcine circovirus type 2 (PCV2) in Pichia pastoris.Results
A truncated cap gene (tcap) with a deleted N-terminal nuclear localization signal was optimized and synthesized. Effective secreted expression was achieved in P. pastoris GS115. The high-productive recombinant strain for tCap was grown in a 5 l bioreactor and the productivity of tCap in supernatant reached 250 μg/ml. Furthermore, serum antibody test demonstrated that adjuvant-assisting tCap induced a significant increase of specific PCV2-Cap antibody over time in mice and a similar antibody level in pigs compared with a commercial Cap-based subunit vaccine.Conclusion
This work establishes a secreted expression strategy in P. pastoris for the production of PCV2 Cap with superior bioactivity, and this strategy might provide potential uses in developing Cap-based subunit vaccine in the future.16.
Masato Tashiro Kiyohide Fushimi Kei Kawano Takahiro Takazono Tomomi Saijo Kazuko Yamamoto Shintaro Kurihara Yoshifumi Imamura Taiga Miyazaki Katsunori Yanagihara Hiroshi Mukae Koichi Izumikawa 《BMC pulmonary medicine》2017,17(1):219
Background
There is conflicting evidence regarding the benefit of adjunctive corticosteroid therapy in patients with Mycoplasma pneumoniae pneumonia. We hypothesised that corticosteroid therapy could reduce mortality and length of stay (LOS) in such patients.Methods
Adult patients with M. pneumoniae pneumonia from January 2010 to December 2013 were identified from the Japanese Diagnosis Procedure Combination inpatient database. The effects of low-dose and high-dose corticosteroid therapies on mortality, LOS, drug costs and hyperglycaemia requiring insulin treatment were evaluated using propensity score analyses.Results
Eligible patients (n?=?2228) from 630 hospitals were divided into no-corticosteroid (n?=?1829), low-dose corticosteroid (n?=?267) and high-dose corticosteroid (n?=?132) groups. The propensity score-matched pairs were generated from no-corticoid and low-dose corticoid groups (251 pairs), or no-corticoid and high-dose corticosteroid groups (120 pairs). Adjunctive corticosteroid therapy did not decrease 30-day mortality. In addition, both low-dose and high-dose corticosteroid therapies were associated with increases in LOS. Furthermore, hyperglycaemia requiring insulin treatment and drug cost increased with corticosteroid use.Conclusions
Adjunctive treatment with low-dose or high-dose corticosteroids may not be beneficial in M. pneumoniae pneumonia.17.
Background
Psoriasis is one of the most common, immune-mediated, chronic inflammatory skin diseases. Proinflammatory cytokines play an important pathogenetic role at a local level.Objective
To assess whether the proinflammatory cytokines IL-1β, IL-6, IL-17, IL-22 and TNF-α are released systemically during psoriasis.Methods
Peripheral blood mononuclear cells (PBMCs) were isolated from 30 patients with psoriasis and 30 healthy volunteers. Cytokine production was assessed in supernatants using an enzyme immunoassay after stimulation of PBMCs with microbial stimuli. In addition, flow cytometry was used to determine the subsets of monocytes involved and the intracellular TNF-α production in monocytes.Results
IL-17 levels were significantly higher in the supernatants of PBMCs from psoriatic patients after stimulation with phytohemagglutinin. TNF-α production was also significantly higher in cells from psoriatic patients after stimulation with all stimuli, as compared with health volunteers. Similar changes were not found for the other cytokines. A statistically significant difference was observed between patients and controls for inflammatory CD14+/CD16+ monocytes (p<0.0001) and patrolling CD14-/CD16+ monocytes.Conclusion
Hyper-production of TNF-α is documented in psoriasis. These results support the concept that there is a systemic, proinflammatory component in psoriasis.18.
Zhengling Liu Zengyan Wang Changhong Hao Yonghui Tian Jingjing Fu 《Reproductive biology and endocrinology : RB&E》2018,16(1):120
Background
Whether adiponectin (ADIPOQ) polymorphisms are associated with the risk of polycystic ovary syndrome (PCOS) remain controversial. Therefore, we performed this study to better explore correlations between ADIPOQ polymorphisms and PCOS risk.Methods
Literature retrieve was conducted in PubMed, Medline and Embase. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.Results
Eighteen studies were enrolled for analyses. Pooled overall analyses showed that rs1501299 polymorphism was significantly associated with PCOS risk (recessive model: p?=?0.02, OR?=?0.77, 95%CI 0.62–0.95; allele model: p?=?0.001, OR?=?1.15, 95%CI 1.06–1.26). Further subgroup analyses according to ethnicity of participants revealed that rs1501299 and rs2241766 polymorphisms were both significantly correlated with PCOS risk in Caucasians. In addition, rs1501299 polymorphism was also significantly correlated with PCOS risk in East Asians.Conclusions
Our findings indicated that rs1501299 and rs2241766 polymorphisms might serve as genetic biomarkers of PCOS in certain ethnicities.19.
Zexi Cai Trine Michelle Villumsen Torben Asp Bernt Guldbrandtsen Goutam Sahana Mogens Sandø Lund 《BMC genetics》2018,19(1):103