Open AccessCrystallization and preliminary structure determination of the transfer protein TraM from the Gram‐positive conjugative plasmid pIP501
Author(s) -
GoessweinerMohr Nikolaus,
Grumet Lukas,
PavkovKeller Tea,
BirnerGruenberger Ruth,
Grohmann Elisabeth,
Keller Walter
Publication year - 2013
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309113000134
Subject(s) - plasmid , bacteria , crystallization , antibiotics , escherichia coli , chemistry , gene transfer , gram negative bacteria , crystallography , gene , microbiology and biotechnology , biology , biochemistry , genetics , organic chemistry
The major means of horizontal gene spread ( e.g. of antibiotic resistance) is conjugative plasmid transfer. It presents a serious threat especially for hospitalized and immuno‐suppressed patients, as it can lead to the accelerated spread of bacteria with multiple antibiotic resistances. Detailed information about the process is available only for bacteria of Gram‐negative (G−) origin and little is known about the corresponding mechanisms in Gram‐positive (G+) bacteria. Here we present the purification, biophysical characterization, crystallization and preliminary structure determination of the TraM C‐terminal domain (TraMΔ, comprising residues 190–322 of the full‐length protein), a putative transfer protein from the G+ conjugative model plasmid pIP501. The crystals diffracted to 2.5 Å resolution and belonged to space group P 1, with unit‐cell parameters a = 39.21, b = 54.98, c = 93.47 Å, α = 89.91, β = 86.44, γ = 78.63° and six molecules per asymmetric unit. The preliminary structure was solved by selenomethionine single‐wavelength anomalous diffraction.