HU proteins are involved in bacterial DNA and RNA repair. Since these proteins are absent in cells of higher organisms, inhibitors of HU proteins can be used as effective and safe antibiotics. The crystallization conditions for the M. gallisepticum HU protein were found and optimized by the vapor-diffusion method. The X-ray diffraction data set was collected to 2.91 Å resolution from the crystals grown by the vapor-diffusion method on a synchrotron source. The crystals of the HU protein belong to sp. gr. P41212 and have the following unit-cell parameters: a = b = 97.94 Å, c = 77.92 Å, α = β = γ = 90°.

В бактериальной системе Escherichia coli осуществлена продукция трех белков из экстремофильных бактерий: гипотетической монооксигеназы из Deinococcus radiodurans, гипотетической нуклеотидилтрансферазы из Thermotoga maritime и гипотетической оксидоредуктазы из Exiguobacterium sibiricum, а также белка-шаперона из Homo sapiens DJ-1. Подобраны условия выделения и очистки рекомбинантных белков, позволяющие получать целевые продукты экспрессии с чистотой не менее 96%. Определены условия кристаллизации, обеспечивающие стабильный рост кристаллов. Проведены рентгеноструктурные эксперименты с целью проверки качества кристаллов; разрешение полученных структурных данных составляло от 1.2 до 1.8 A.

Selected proteins were produced in Escherichia coli bacterial expression system--three proteins from extremophil bacteria: a putative monooxygenase from Deinococcus radiodurans, a putative nucleotidyltransferase from Thermotoga maritima, a putative oxidoreductase from Exiguobacterium sibiricum; and a shaperon from Homo sapiens DJ-1. The protocol of isolation & purification of recombinant proteins were developed that allowed to obtain expression products with the purity of no less than 96%. Conditions for the crystallization have been selected that allowed a stable growth of crystals. Preliminary x-ray experiments were conducted in order to confirm the quality of produced crystals; the resolution of obtained structural data was from 1.2 to 1.8 angstrom.

Three proteins from extremophilic bacteria—hypothetical monooxygenase from Deinococcus radiodurans , hypothetical nucleotidyl transferase from Thermotoga maritime , and hypothetical oxidoreductase from Exiguobacterium sibiricum —and the DJ-1 chaperone protein from Homo sapiens have been produced in Escherichia coli . The isolation and purification procedures developed for the recombinant proteins allowed us to achieve yields higher than 96%. Crystallization conditions enabling stable growth of crystals have been determined. X-ray experiments have been performed to test the quality of the crystals and the resolution achieved ranged from 1.2 to 1.8 Å.