• 主页
  • 查找结果
  • Spectroscopic evidence for a 5-coordinate oxygenic ligated high spin ferric heme moiety in the Neisseria meningitidis hemoglobin binding receptor.

Spectroscopic evidence for a 5-coordinate oxygenic ligated high spin ferric heme moiety in the Neisseria meningitidis hemoglobin binding receptor.

Biochimica et biophysica acta (2014-06-28)
David Z Mokry, Angela Nadia-Albete, Michael K Johnson, Gudrun S Lukat-Rodgers, Kenton R Rodgers, William N Lanzilotta
摘要

For many pathogenic microorganisms, iron acquisition represents a significant stress during the colonization of a mammalian host. Heme is the single most abundant source of soluble iron in this environment. While the importance of iron assimilation for nearly all organisms is clear, the mechanisms by which heme is acquired and utilized by many bacterial pathogens, even those most commonly found at sites of infection, remain poorly understood. An alternative protocol for the production and purification of the outer membrane hemoglobin receptor (HmbR) from the pathogen Neisseria meningitidis has facilitated a biophysical characterization of this outer membrane transporter by electronic absorption, circular dichroism, electron paramagnetic resonance, and resonance Raman techniques. HmbR co-purifies with 5-coordinate high spin ferric heme bound. The heme binding site accommodates exogenous imidazole as a sixth ligand, which results in a 6-coordinate, low-spin ferric species. Both the 5- and 6-coordinate complexes are reduced by sodium hydrosulfite. Four HmbR variants with a modest decrease in binding efficiency for heme have been identified (H87C, H280A, Y282A, and Y456C). These findings are consistent with an emerging paradigm wherein the ferric iron center of bound heme is coordinated by a tyrosine ligand. In summary, this study provides the first spectroscopic characterization for any heme or iron transporter in Neisseria meningitidis, and suggests a coordination environment heretofore unobserved in a TonB-dependent hemin transporter. A detailed understanding of the nutrient acquisition pathways in common pathogens such as N. meningitidis provides a foundation for new antimicrobial strategies.

材料
货号
品牌
产品描述

Sigma-Aldrich
铁, ≥99%, reduced, powder (fine)
Sigma-Aldrich
铁, powder, −325 mesh, 97%
Sigma-Aldrich
羰基铁, ≥97% Fe basis
Sigma-Aldrich
铁, powder, <10 μm, ≥99.9% trace metals basis
Sigma-Aldrich
铁, puriss. p.a., carbonyl-Iron powder, low in magnesium and manganese compounds, ≥99.5% (RT)
Sigma-Aldrich
铁, flakes, ≥99.99% trace metals basis
Sigma-Aldrich
铁, nanopowder, 35-45 nm particle size, 99.5% trace metals basis
Sigma-Aldrich
铁, granular, 10-40 mesh, >99.99% trace metals basis
Sigma-Aldrich
铁, chips, 99.98% trace metals basis
Sigma-Aldrich
铁, foil, thickness 0.1 mm, ≥99.9% trace metals basis
Sigma-Aldrich
铁, foil, thickness 0.25 mm, ≥99.99% trace metals basis
Sigma-Aldrich
铁, wire, diam. 1.0 mm, ≥99.9% trace metals basis
Sigma-Aldrich
铁, carbon coated magnetic, nanopowder, 25 nm avg. part. size, 99.5% trace metals basis
Sigma-Aldrich
铁, wire, diam. 0.5 mm, ≥99.9% trace metals basis
Sigma-Aldrich
铁, rod, diam. 6.3 mm, 99.98% trace metals basis
铁, IRMM®, certified reference material, 0.5 mm wire
铁, foil, 300x300mm, thickness 0.1mm, hard, 99.5%
铁, foil, 0.2m coil, thickness 0.5mm, coil width 49mm, armco« soft ingot 99.8+%
铁, wire reel, 1m, diameter 0.025mm, as drawn, 99.99+%
铁, wire reel, 20m, diameter 0.125mm, hard, 99.5%
铁, foil, 10mm disks, thickness 0.01mm, 99.85%
铁, foil, 10mm disks, thickness 0.01mm, 99.99+%
铁, foil, 10mm disks, thickness 0.020mm, 99.85%
铁, foil, 10mm disks, thickness 0.025mm, as rolled, 99.99+%
铁, foil, 10mm disks, thickness 0.025mm, hard, 99.5%
铁, foil, 10mm disks, thickness 0.038mm, hard, 99.5%
铁, foil, 10mm disks, thickness 0.05mm, as rolled, 99.99+%
铁, foil, 10mm disks, thickness 0.05mm, hard, 99.5%
铁, foil, 10mm disks, thickness 0.075mm, as rolled, 99.99+%
铁, foil, 10mm disks, thickness 0.075mm, hard, 99.5%

社交媒体

LinkedIn icon
Twitter icon
Facebook Icon
Instagram Icon

Merck

科研、开发、生产。

作为生命科学行业的全球领先供应商,我们致力于为科研、生物技术开发和生产,以及制药药物疗法开发和生产提供各类解决方案和服务。

© 2021年版权归德国达姆施塔特默克集团(Merck KGaA)及/或其附属公司所有。版权所有。

未经许可,严禁复制本网站上的任何资料。