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Holck J, Larsen DM, Michalak M, Li H, Kjærulff L, Kirpekar F, Gotfredsen CH, Forssten S, Ouwehand AC, Mikkelsen JD, Meyer AS. Enzyme catalysed production of sialylated human milk oligosaccharides and galactooligosaccharides by Trypanosoma cruzi trans-sialidase. N Biotechnol 2014; 31:156-65. [DOI: 10.1016/j.nbt.2013.11.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 11/25/2013] [Accepted: 11/26/2013] [Indexed: 10/25/2022]
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Michalak M, Larsen DM, Jers C, Almeida JR, Willer M, Li H, Kirpekar F, Kjærulff L, Gotfredsen CH, Nordvang RT, Meyer AS, Mikkelsen JD. Biocatalytic production of 3′-sialyllactose by use of a modified sialidase with superior trans-sialidase activity. Process Biochem 2014. [DOI: 10.1016/j.procbio.2013.10.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Jers C, Michalak M, Larsen DM, Kepp KP, Li H, Guo Y, Kirpekar F, Meyer AS, Mikkelsen JD. Rational design of a new Trypanosoma rangeli trans-sialidase for efficient sialylation of glycans. PLoS One 2014; 9:e83902. [PMID: 24404142 PMCID: PMC3880268 DOI: 10.1371/journal.pone.0083902] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 11/18/2013] [Indexed: 12/23/2022] Open
Abstract
This paper reports rational engineering of Trypanosoma rangeli sialidase to develop an effective enzyme for a potentially important type of reactivity: production of sialylated prebiotic glycans. The Trypanosoma cruzi trans-sialidase and the homologous T. rangeli sialidase has previously been used to investigate the structural requirements for trans-sialidase activity. We observed that the T. cruzi trans-sialidase has a seven-amino-acid motif (197–203) at the border of the substrate binding cleft. The motif differs substantially in chemical properties and substitution probability from the homologous sialidase, and we hypothesised that this motif is important for trans-sialidase activity. The 197–203 motif is strongly positively charged with a marked change in hydrogen bond donor capacity as compared to the sialidase. To investigate the role of this motif, we expressed and characterised a T. rangeli sialidase mutant, Tr13. Conditions for efficient trans-sialylation were determined, and Tr13's acceptor specificity demonstrated promiscuity with respect to the acceptor molecule enabling sialylation of glycans containing terminal galactose and glucose and even monomers of glucose and fucose. Sialic acid is important in association with human milk oligosaccharides, and Tr13 was shown to sialylate a number of established and potential prebiotics. Initial evaluation of prebiotic potential using pure cultures demonstrated, albeit not selectively, growth of Bifidobacteria. Since the 197–203 motif stands out in the native trans-sialidase, is markedly different from the wild-type sialidase compared to previous mutants, and is shown here to confer efficient and broad trans-sialidase activity, we suggest that this motif can serve as a framework for future optimization of trans-sialylation towards prebiotic production.
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Affiliation(s)
- Carsten Jers
- Center for BioProcess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Lyngby, Denmark
| | - Malwina Michalak
- Center for BioProcess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Lyngby, Denmark
| | - Dorte M. Larsen
- Center for BioProcess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Lyngby, Denmark
| | - Kasper P. Kepp
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
| | - Haiying Li
- Department of Biochemistry and Molecular Biology, Southern University of Denmark, Odense, Denmark
| | - Yao Guo
- Center for BioProcess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Lyngby, Denmark
| | - Finn Kirpekar
- Department of Biochemistry and Molecular Biology, Southern University of Denmark, Odense, Denmark
| | - Anne S. Meyer
- Center for BioProcess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Lyngby, Denmark
| | - Jørn D. Mikkelsen
- Center for BioProcess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Lyngby, Denmark
- * E-mail:
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Silva IR, Larsen DM, Jers C, Derkx P, Meyer AS, Mikkelsen JD. Enhancing RGI lyase thermostability by targeted single point mutations. Appl Microbiol Biotechnol 2013; 97:9727-35. [DOI: 10.1007/s00253-013-5184-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 08/07/2013] [Accepted: 08/10/2013] [Indexed: 11/25/2022]
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Larsen DM, Haberichter SL, Gill JC, Shapiro AD, Flood VH. Variability in platelet- and collagen-binding defects in type 2M von Willebrand disease. Haemophilia 2013; 19:590-4. [PMID: 23496210 DOI: 10.1111/hae.12117] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/14/2013] [Indexed: 11/28/2022]
Abstract
Type 2M von Willebrand disease (VWD) includes qualitative defects in von Willebrand factor (VWF) function, with normal multimer distribution but a defect in VWF activity with respect to platelet or collagen binding. We characterized novel VWF gene mutations found in type 2M VWD subjects enrolled in the Zimmerman Program for the Molecular and Clinical Biology of VWD. Subjects were enrolled based on a pre-existing diagnosis of type 2M VWD. Testing included full-length gene sequencing, VWF antigen (VWF:Ag), VWF ristocetin cofactor activity (VWF:RCo), VWF collagen binding and multimer distribution. Recombinant VWF variants were synthesized using site-directed mutagenesis and expressed in HEK293T cells. Platelet binding was measured by flow cytometry with fixed platelets and ELISA with recombinant glycoprotein Ibα (GPIbα). Four novel VWF A1 domain mutations were found in individuals with type 2M VWD: S1358N, S1387I, S1394F and Q1402P. All subjects had a history of bleeding, VWF:RCo < 40 IU dL(-1) , VWF:RCo/VWF:Ag ratios <0.6 and normal multimer distribution. No defect in expression, secretion, or multimerization was found for any of the mutations. All showed decreased binding to intact platelets, and decreased or absent binding to a mutant GPIbα construct with spontaneous VWF binding. 1387I had decreased binding to all collagen types tested. 1402P had reduced binding exclusively to type VI collagen. Type 2M VWD is a heterogeneous category comprised of both collagen- and platelet-binding defects. Understanding the precise defect for each mutation may ultimately lead to better diagnosis and treatment.
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Affiliation(s)
- D M Larsen
- Medical College of Wisconsin, Milwaukee, WI, USA
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Thomassen LV, Larsen DM, Mikkelsen JD, Meyer AS. Definition and characterization of enzymes for maximal biocatalytic solubilization of prebiotic polysaccharides from potato pulp. Enzyme Microb Technol 2011; 49:289-97. [PMID: 22112514 DOI: 10.1016/j.enzmictec.2011.06.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Revised: 05/17/2011] [Accepted: 06/06/2011] [Indexed: 11/25/2022]
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Ma T, Ren PG, Larsen DM, Suenaga E, Zilber S, Genovese M, Smith RL, Goodman SB. Efficacy of a p38 mitogen activated protein kinase inhibitor in mitigating an established inflammatory reaction to polyethylene particles in vivo. J Biomed Mater Res A 2008; 89:117-23. [PMID: 18431764 DOI: 10.1002/jbm.a.31957] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The inhibitor of p38 mitogen-activated protein kinase (MAPK) is of interest in the nonoperative treatment of periprosthetic osteolysis due to wear particles. Previous studies demonstrated that an oral p38 MAPK inhibitor did not suppress bone formation when given during the initial phase of tissue differentiation. However, the oral p38 MAPK inhibitor also did not curtail the foreign body and chronic inflammatory response to particles when given simultaneously. The purpose of the current study was to examine the efficacy of a p38 MAPK inhibitor, SCIO-323, on mitigating an established inflammatory reaction that parallels the clinical situation more closely. The Bone Harvest Chamber was implanted in rabbits and submicron polyethylene particles were placed in the chamber for 6 weeks. The contents of the chambers were harvested every 6 weeks. Oral treatment with the SCIO-323 included delivery for 3 weeks and stopping for 3 weeks, delivery for 3 weeks after an initial 3-week delay, and delivery for 6 weeks continuously. Administration of the SCIO-323 continuously for 6 weeks with/without the presence of particles, or for the initial 3 of 6 weeks had minor effects on bone ingrowth. After establishing a particle-induced chronic inflammatory reaction for 3 weeks, administration of SCIO-323 for a subsequent 3 weeks suppressed net bone formation. The activity of osteoclast-like cells remained low among all treatments when compared with the first control. Using the present model, the oral p38 MAPK inhibitor was ineffective in improving bone ingrowth in the presence of polyethylene particles.
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Affiliation(s)
- T Ma
- Department of Orthopaedic Surgery, Stanford University, Stanford, California, USA
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Ma T, Nelson ER, Mawatari T, Oh KJ, Larsen DM, Smith RL, Goodman SB. Effects of local infusion of OP-1 on particle-induced and NSAID-induced inhibition of bone ingrowth in vivo. J Biomed Mater Res A 2007; 79:740-6. [PMID: 16988970 DOI: 10.1002/jbm.a.30949] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Excessive polyethylene wear particles from joint replacements may lead to periprosthetic osteolysis and loosening. Nonsteroidal anti-inflammatory drugs (NSAIDs) decrease fracture healing and bone ingrowth. We hypothesized that continuous local infusion of OP-1 (BMP-7) would increase local bone formation in the presence of two different adverse stimuli, polyethylene particles, and an oral NSAID. The Drug Test Chamber (DTC) was implanted in the proximal tibia of mature rabbits. The tissue growing into the chamber was exposed to OP-1 solution (110 ng/day), which was infused via an osmotic pump. Infusion of OP-1 alone for 6 weeks enhanced local bone formation in the chamber by 80% (p < 0.05) over infusion of carrier alone. In the presence of polyethylene particles, infusion of OP-1 increased local bone formation by 38% (p < 0.05) over treatment with particles and carrier. Oral administration of NSAID reduced local bone formation by 58% (p < 0.05); this suppressive effect caused by NSAIDS was completely reversed by the infusion of OP-1 (p < 0.05). These findings underline a potential role for local treatment with OP-1 to increase bone formation in the presence of potentially adverse stimuli such as polyethylene wear particles or NSAID use.
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Affiliation(s)
- T Ma
- Department of Orthopaedic Surgery, Stanford University, Stanford, California, USA
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Larsen DM. Effect of intersite electron-electron interaction on the concentration of D- ions in quantum wells. Phys Rev B Condens Matter 1996; 53:15719-15726. [PMID: 9983407 DOI: 10.1103/physrevb.53.15719] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Mueller ER, Larsen DM, Goodhue WD, Waldman J. Band nonparabolicity and central-cell corrections for D- centers in GaAs quantum wells. Phys Rev B Condens Matter 1995; 51:2326-2333. [PMID: 9978985 DOI: 10.1103/physrevb.51.2326] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Mueller ER, Larsen DM, Waldman J, Goodhue WD. Erratum: Effects of band nonparabolicity and central-cell corrections on the spectrum of Si donors in GaAs quantum wells. Phys Rev B Condens Matter 1994; 50:11287. [PMID: 9986931 DOI: 10.1103/physrevb.50.11287.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Mueller ER, Larsen DM, Waldman J, Goodhue WD. Effects of band nonparabolicity and central-cell corrections on the spectrum of Si donors in GaAs quantum wells. Phys Rev B Condens Matter 1994; 49:13475-13482. [PMID: 10010283 DOI: 10.1103/physrevb.49.13475] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Larsen DM, McCann SY. Energies of p-like and d-like states of the H- ion in magnetic fields. Phys Rev B Condens Matter 1993; 47:13175-13179. [PMID: 10005621 DOI: 10.1103/physrevb.47.13175] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Larsen DM, McCann SY. Variational studies of two- and three-dimensional D- centers in magnetic fields. Phys Rev B Condens Matter 1992; 46:3966-3970. [PMID: 10004125 DOI: 10.1103/physrevb.46.3966] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Mueller ER, Larsen DM, Waldman J, Goodhue WD. Definitive identification of D- centers in GaAs quantum wells by tilt-induced line splitting in a magnetic field. Phys Rev Lett 1992; 68:2204-2207. [PMID: 10045333 DOI: 10.1103/physrevlett.68.2204] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Mueller ER, Goodhue WD, Larsen DM, Bales JW, Waldman J. Magneto-optical study of donor-level crossing in tipped GaAs/(Ga,Al)As quantum wells. Phys Rev B Condens Matter 1991; 44:1754-1761. [PMID: 9999710 DOI: 10.1103/physrevb.44.1754] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Brozak G, McCombe BD, Larsen DM. Potential and magnetic field confinement of shallow donor impurities in semiconductor quantum wells. Phys Rev B Condens Matter 1989; 40:1265-1270. [PMID: 9991952 DOI: 10.1103/physrevb.40.1265] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Hodby JW, Russell GP, Peeters FM, Devreese JT, Larsen DM. Cyclotron resonance of polarons in the silver halides: AgBr and AgCl. Phys Rev Lett 1987; 58:1471-1474. [PMID: 10034445 DOI: 10.1103/physrevlett.58.1471] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Larsen DM. Fourth-order perturbation calculation of the cyclotron resonance frequency of the two-dimensional polaron. Phys Rev B Condens Matter 1987; 35:4427-4434. [PMID: 9941997 DOI: 10.1103/physrevb.35.4427] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Larsen DM. Comment on "Band nonparabolicity effects on weak-coupling polarons in compound semiconductors". Phys Rev B Condens Matter 1986; 34:5927-5928. [PMID: 9940442 DOI: 10.1103/physrevb.34.5927] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Youngdale ER, Larsen DM, Aggarwal RL. Observation of anticrossing between Zeeman-split 1s(T2) states of opposite spin for As donors in germanium. Phys Rev B Condens Matter 1985; 32:3938-3946. [PMID: 9937547 DOI: 10.1103/physrevb.32.3938] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Larsen DM. Upper bound to the polaron ground state in a magnetic field using the Feynman path-integral method. Phys Rev B Condens Matter 1985; 32:2657-2658. [PMID: 9937354 DOI: 10.1103/physrevb.32.2657] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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Abstract
Four distinct collisionless excitation processes are observed when SF(6) molecules are illuminated simultaneously by "weak" continuously tunable cw probe radiation and by "strong" pulsed-pump radiation. These processes are identified by studying the line shape, frequency, and temporal decay of the change in transmitted probe intensity induced by the pump pulse. The significance of this work for the spectroscopy of high vibrational levels and for collisionless dissociation is discussed briefly.
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Affiliation(s)
- P F Moulton
- Lincoln Laboratory, Massachusetts Institute of Technology, Lexington, Massachusetts 02173, USA
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