187,006 research outputs found
Expanding the set of rhodococcal Baeyer–Villiger monooxygenases by high-throughput cloning, expression and substrate screening
No full textTo expand the available set of Baeyer–Villiger monooxygenases (BVMOs), we have created expression constructs for producing 22 Type I BVMOs that are present in the genome of Rhodococcus jostii RHA1. Each BVMO has been probed with a large panel of potential substrates. Except for testing their substrate acceptance, also the enantioselectivity of some selected BVMOs was studied. The results provide insight into the biocatalytic potential of this collection of BVMOs and expand the biocatalytic repertoire known for BVMOs. This study also sheds light on the catalytic capacity of this large set of BVMOs that is present in this specific actinomycete. Furthermore, a comparative sequence analysis revealed a new BVMO-typifying sequence motif. This motif represents a useful tool for effective future genome mining efforts.
Genome Sequence of Stenotrophomonas maltophilia PML168, Which Displays Baeyer-Villiger Monooxygenase Activity
No full textStenotrophomonas maltophilia PML168 was isolated from Wembury Beach on the English Coast from a rock pool following growth and selection on agar plates. Here we present the permanent draft genome sequence, which has allowed prediction of function for several genes encoding enzymes relevant to industrial biotechnology, including a novel flavoprotein monooxygenase.</p
Detection of latent tuberculosis in immunosuppressed patients with autoimmune diseases: performance of a Mycobacterium tuberculosis antigen-specific interferon gamma assay
No full textOBJECTIVE: To analyse the performance of a new M. tuberculosis-specific interferon gamma (IFNgamma) assay in patients with chronic inflammatory diseases who receive immunosuppressive drugs, including tumour necrosis factor alpha (TNFalpha) inhibitors. METHODS: Cellular immune responses to the M. tuberculosis-specific antigens ESAT-6, CFP-10, TB7.7 were prospectively studied in 142 consecutive patients treated for inflammatory rheumatic conditions. Results were compared with tuberculin skin tests (TSTs). Association of both tests with risk factors for latent M. tuberculosis infection (LTBI) and BCG vaccination were determined and the influence of TNFalpha inhibitors, corticosteroids, and disease modifying antirheumatic drugs (DMARDs) on antigen-specific and mitogen-induced IFNgamma secretion was analysed. RESULTS: 126/142 (89%) patients received immunosuppressive therapy. The IFNgamma assay was more closely associated with the presence of risk factors (odds ratio (OR) = 23.8 (95% CI 5.14 to 110) vs OR = 2.77 (1.22 to 6.27), respectively; p = 0.009), but less associated with BCG vaccination than the TST (OR = 0.47 (95% CI 0.15 to 1.47) vs OR = 2.44 (0.74 to (8.01), respectively; p = 0.025). Agreement between the IFNgamma assay and TST results was low (kappa = 0.17; 95% CI 0.02 to 0.32). The odds for a positive IFNgamma assay strongly increased with increasing prognostic relevance of LTBI risk factors. Neither corticosteroids nor conventional DMARDs significantly affected IFNgamma responses, but the odds for a positive IFNgamma assay were decreased in patients treated with TNFalpha inhibitors (OR = 0.21 (95% CI 0.07 to 0.63), respectively; p = 0.006). CONCLUSIONS: These results demonstrate that the performance of the M. tuberculosis antigen-specific IFNgamma ELISA is better than the classic TST for detection of LTBI in patients receiving immunosuppressive therapy for treatment of systemic autoimmune disorders
Burchard Villiger, S.J. (3 of 18)
No full textContains ALS to B. Villiger from: Rev. P. Lavialle offering St. Mary's College, KY to Society 4/2/1859; P. Healy on misc., political situation in Italy 5/22/1859, misc. in Belgium 9/18/1859; various senders on misc. Jan-Jun 1859; Joseph Hegan, SJ on trip to Europe 9/22/1859, on arrival at Havre 10/3/1859; Murphy on faculty needs at Fordham 7/17/1859; Rev. B. Keller requesting Jesuit for Camp Floyd, Utah 6/20 & 9/1/1859; Sopranis announcing appointment as Visitor and beginning of Visitation 10/2/1859; Fr. Coppens on sending Scholastics to Louvain 7/6/1859; Rev. George Browne on Moore's illness in Canada 10/10/1859; Beckx on removal of prayer from litanies (undated)**Former finding aid locations: 119_76_36; 226Z1-226Z9*
Baeyer-Villiger oxidation of aliphatic ketones.
No full textBaeyer-Villiger oxidation of aliphatic ketones.</p
Baeyer-Villiger Oxidation of Ketones Catalyzed by Platinum(II) Lewis Acid Complexes Containing Coordinated Electron-poor Fluorinated Diphosphines
No full textNew hydroxo-bridged platinum(II) complexes of the type [P(μ-OH)(P-P)]2[BF4]2, containing fluorinated diphosphines, are used in the Baeyer−Villiger oxidation of 2-methylcyclohexanone using 35% hydrogen peroxide as oxidant. IR data of the isocyanide group in complexes of the type [PtCl(CN-2,6-(CH3)2C6H3)(P-P)][BF4] have allowed us to investigate the Lewis acidity of the complexes. A correlation is found between the electrophilicity of the metal center and the catalytic activity of complexes in the Baeyer−Villiger oxidation of ketones
Enantioselective Baeyer-Villiger oxidation catalyzed by palladium(II) complexes with chiral P,N-ligands
No full textAsymmetric Baeyer-Villiger reaction of symmetrical cyclobutanones 1a-j with urea-hydrogen peroxide (UHP) can be catalyzed by a complex of Pd(II) and the new terpene-derived P,N-ligand 7. The resulting lactones 2a-j were obtained in high yields and with good enantioselectivity (<= 81% ee)
Baeyer-Villiger oxidation of aryl ketones and aldehydes.
No full textBaeyer-Villiger oxidation of aryl ketones and aldehydes.</p
Pregnancy induces numerical and functional changes of CD4+CD25high regulatory T cells in patients with rheumatoid arthritis
No full textOBJECTIVE: In a prospective study we investigated whether numerical and functional changes of CD4+CD25(high) regulatory T cells (Treg) were associated with changes of disease activity observed during pregnancy and post partum in patients with rheumatoid arthritis (RA). METHODS: The frequency of CD4+CD25(high) T cells was determined by flow cytometry in 12 patients with RA and 14 healthy women during and after pregnancy. FACS-sorted CD4+CD25(high) T cells and CD4+CD25- T cells were stimulated with anti-CD3 and anti-CD28 monoclonal antibodies alone or in co-culture to investigate proliferation and cytokine secretion. RESULTS: Frequencies of CD4+CD25(high) Treg were significantly higher in the third trimester compared to 8 weeks post-partum both in patients and controls. Numbers of CD4+CD25(high) Treg inversely correlated with disease activity in the third trimester and post-partum. In co-culture experiments significantly higher amounts of IL-10 and lowered levels of TNFalpha and IFNgamma were found in supernatants of the third trimester compared to post-partum samples. These findings were independent from health or disease in pregnancy, however post-partum TNFalpha and IFNgamma levels were higher in patients with disease flares. CONCLUSION: The amelioration of disease activity in the third trimester corresponded to the increased number of Treg that induced a pronounced anti-inflammatory cytokine milieu. The pregnancy related quantitative and qualitative changes of Treg suggest a beneficial effect of Treg on disease activity
Baeyer-Villiger Monooxygenases:Tunable Oxidative Biocatalysts
No full textPollution, accidents, and misinformation have earned the pharmaceutical and chemical industry a poor public reputation, despite their undisputable importance to society. Biotechnological advances hold the promise to enable a future of drastically reduced environmental impact and rigorously more efficient production routes at the same time. This is exemplified in the Baeyer-Villiger reaction, which offers a simple synthetic route to oxidize ketones to esters, but application is hampered by the requirement of hazardous and dangerous reagents. As an attractive alternative, flavin-containing Baeyer-Villiger monooxygenases (BVMOs) have been investigated for their potential as biocatalysts for a long time, and many variants have been characterized. After a general look at the state of biotechnology, we here summarize the literature on biochemical characterizations, mechanistic and structural investigations, as well as enzyme engineering efforts in BVMOs. With a focus on recent developments, we critically outline the advances toward tuning these enzymes suitable for industrial applications.</p
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