Abstract

We developed a spectrometer for pulsed ENDOR at 140 GHz, which is based on three new main units a magnet utilizing a 1 0.4 T superconducting sweep coil and a 2 H-NMR field lock system, a 139.5 GHz microwave bridge with four phase capabilities operating in reflection mode, and a probe for EPR/NMR double resonance. The probe consists of a TEOI I cavity adapted for RF irradiation and a high-quality resonance circuit with autotuning capability for variable radio frequency irradiation. For pulsed EPR we obtain 90* pulses of 60 - 70 ns and an absolute sensitivity of 3.109 spins/Gauss at 20 K. The performance of the spectrometer was demonstrated with pulsed ENDOR spectra of a standard bis-diphenylene-phenyl-allyl (BDPA) doped into polystyrene and of the tyrosyl radical from E. coli Ribonucleotide Reductase (RNR). The EPR spectrum of the RNR tyrosyl radical displays substantial g-anisotropy at 5 T and was used to demonstrate orientation selective Davies-ENDOR.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Biotechnology Resource Grants (P41)
Project #
2P41RR000995-24
Application #
6118649
Study Section
Project Start
1999-05-15
Project End
2000-04-30
Budget Start
1998-10-01
Budget End
1999-09-30
Support Year
24
Fiscal Year
1999
Total Cost
Indirect Cost

  Institution

Name
Massachusetts Institute of Technology
Department
Type
DUNS #
City
Cambridge
State
MA
Country
United States
Zip Code
02139

  Publications

Marintchev, Assen; Edmonds, Katherine A; Marintcheva, Boriana et al. (2009) Topology and regulation of the human eIF4A/4G/4H helicase complex in translation initiation. Cell 136:447-60
Frueh, Dominique P; Arthanari, Haribabu; Koglin, Alexander et al. (2009) A double TROSY hNCAnH experiment for efficient assignment of large and challenging proteins. J Am Chem Soc 131:12880-1
Frueh, Dominique P; Leed, Alison; Arthanari, Haribabu et al. (2009) Time-shared HSQC-NOESY for accurate distance constraints measured at high-field in (15)N-(13)C-ILV methyl labeled proteins. J Biomol NMR 45:311-8
Lentz, Margaret R; Westmoreland, Susan V; Lee, Vallent et al. (2008) Metabolic markers of neuronal injury correlate with SIV CNS disease severity and inoculum in the macaque model of neuroAIDS. Magn Reson Med 59:475-84
Hyberts, Sven G; Heffron, Gregory J; Tarragona, Nestor G et al. (2007) Ultrahigh-resolution (1)H-(13)C HSQC spectra of metabolite mixtures using nonlinear sampling and forward maximum entropy reconstruction. J Am Chem Soc 129:5108-16
Chen, Jingyang; Dupradeau, Francois-Yves; Case, David A et al. (2007) Nuclear magnetic resonance structural studies and molecular modeling of duplex DNA containing normal and 4'-oxidized abasic sites. Biochemistry 46:3096-107
Lentz, Margaret R; Kim, John P; Westmoreland, Susan V et al. (2005) Quantitative neuropathologic correlates of changes in ratio of N-acetylaspartate to creatine in macaque brain. Radiology 235:461-8
Kim, John P; Lentz, Margaret R; Westmoreland, Susan V et al. (2005) Relationships between astrogliosis and 1H MR spectroscopic measures of brain choline/creatine and myo-inositol/creatine in a primate model. AJNR Am J Neuroradiol 26:752-9
Peled, S; Cory, D G; Raymond, S A et al. (1999) Water diffusion, T(2), and compartmentation in frog sciatic nerve. Magn Reson Med 42:911-8
Mo, H; Dai, Y; Pochapsky, S S et al. (1999) 1H, 13C and 15N NMR assignments for a carbon monoxide generating metalloenzyme from Klebsiella pneumoniae. J Biomol NMR 14:287-8

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