AI Article Synopsis
- The outer membrane protein A from Klebsiella pneumoniae was studied using NMR to determine its three-dimensional structure, making it one of the largest integral membrane proteins analyzed so far.
- The protein plays a significant role in immune responses and serves as an effective carrier protein, with a total of 210 amino acids.
- The structure was refined using 920 experimental constraints, producing 20 optimal structures with minimal deviation in the core beta-barrel region, and the protein dynamics were investigated over various timescales.
Article Abstract
The three-dimensional structure of the outer membrane protein A from Klebsiella pneumoniae transmembrane domain was determined by NMR.This protein induces specific humoral and cytotoxic responses, and is a potent carrier protein. This is one of the largest integral membrane proteins(210 residues) for which nearly complete resonance assignment, including side chains, has been achieved so far. The methodology rested on the use of 900 MHz 3D and 4D TROSY experiments recorded on a uniformly 15N,13C,2H-labeled sample and on a perdeuterated methyl protonated sample. The structure was refined from 920 experimental constraints, giving an ensemble of 20 best structures with an r.m.s. deviation of 0.54 A for the main chain atoms in the core eight-stranded beta-barrel. The protein dynamics was assessed, in a residue-specific manner, by 1H-15N NOEs (pico- to nanosecond timescale), exchange broadening (millisecond to second) and 1H-2H chemical exchange (hour-weeks).
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| http://dx.doi.org/10.1016/j.jmb.2008.10.021 | DOI Listing |
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