Deinococcus radiodurans mutant lacking pyrroloquinoline–quinone (PQQ) synthesis shows sensitivity to g-rays and impairment of DNA double strand break repair. The genome of this bacterium encodes five putative proteins having multiple PQQ binding motifs. The deletion mutants of corresponding genes were generated, and their response to DNA damage was monitored. Only the Ddr2518 mutant exhibited h...

The DR2518 (RqkA) a eukaryotic type serine/threonine protein kinase in Deinococcus radiodurans was characterized for its role in bacterial response to oxidative stress and DNA damage. The K42A, S162A, T169A and S171A mutation in RqkA differentially affected its kinase activity and functional complementation for γ radiation resistance in Δdr2518 mutant. For example, K42A mutant was completely in...

In the hierarchy of cellular targets damaged by ionizing radiation (IR), classical models of radiation toxicity place DNA at the top. Yet, many prokaryotes are killed by doses of IR that cause little DNA damage. Here we have probed the nature of Mn-facilitated IR resistance in Deinococcus radiodurans, which together with other extremely IR-resistant bacteria have high intracellular Mn/Fe concen...

Deinococcus radiodurans exhibits extreme resistance to DNA damage and is one of only few bacteria that encode two Dps (DNA protection during starvation) proteins. Dps-1 was shown previously to bind DNA with high affinity and to localize to the D. radiodurans nucleoid. A unique feature of Dps-2 is its predicted signal peptide. In the present paper, we report that Dps-2 assembly into a dodecamer ...

THREE-DIMENSIONAL STRUCTURES OF S-LAYERS 1. Classification of S-layers According to Symmetry 2. Hexagonal S-layers (a) Sulfolobus acidocaldarius (b) Thermoproteus tenax (c) Synechocystis sp. CLII (d) Eubacterium sp. AHN 990 (e) Clostridium thermohydrosulfuricum (f) Deinococcus radiodurans (g) Aquaspirillum serpens (h) Acetooenium kivui (i) Bacteroides buccae 3. Tetragonal S-layers (a) Bacillus ...

We have developed a novel chromatography for the rapid isolation of active ribosomes from bacteria without the use of harsh conditions or lengthy procedures that damage ribosomes. Ribosomes interact with an alkyl linker attached to the resin, apparently through their RNA component. Examples are given with ribosomes from Escherichia coli, Deinococcus radiodurans, and with clinical isolates of St...

The classical dogma of radiation biology asserts that the cytotoxic effects of ionizing radiation (IR) are principally the result of DNA damage. Yet many organisms that encode a complement of DNA repair functions are killed by IR doses that cause little DNA damage. Instead, proteins likely are the first major class of molecules damaged by IR. This article presents a new perspective on extreme I...

A whole-genome restriction map of Deinococcus radiodurans, a radiation-resistant bacterium able to survive up to 15,000 grays of ionizing radiation, was constructed without using DNA libraries, the polymerase chain reaction, or electrophoresis. Very large, randomly sheared, genomic DNA fragments were used to construct maps from individual DNA molecules that were assembled into two circular over...

Through the analysis of 57 bacterial genomes we have detected repetitive extragenic palindromic DNA sequences (REPs) in 11 species. For a sequence to be considered as REP, the following criteria should be met: (i) It should be extragenic, (ii) palindromic, (iii) of a length between 21 and 65 bases and (iv) should constitute more than 0.5% of the total extragenic space. Species-specific REPs hav...