Selective Photoinduced Dimerization and Slow Recovery of a BLUF Domain of EB1.

The EAL-BLUF fragment from BldP1 (EB1) light-dependently hydrolyzes c-di-GMP. Herein, the photoreaction of the BLUF domain of EB1 (eBLUF) is studied. It is found for the first time that a monomeric BLUF domain forms a dimer upon illumination and its dark recovery is very slow.

Enzymatic activity of the blue light-regulated phosphodiesterase BlrP1 from Klebsiella pneumoniae shows a nonlinear dependence on light intensity.

The blue light-regulated phosphodiesterase BlrP1 from Klebsiella pneumoniae hydrolyzes cyclic dimeric guanosine monophosphate (GMP) in a blue light-dependent manner. It contains a photosensing BLUF domain and a functional EAL domain. Previously, it was reported that conformational changes in the dimer upon light illumination occurred only when both protomers of the dimer were excited.

Photoreaction of BlrP1: the role of a nonlinear photo-intensity sensor.

Blue-light-regulated phosphodiesterase 1 (BlrP1) is a blue light sensor protein that controls the hydrolysis of cyclic dimeric guanosine monophosphate, which regulates cellular motility, virulence, and formation of biofilms. In this report, the photoreaction dynamics of BlrP1 and its blue light sensor using a flavin adenine dinucleotide (BLUF) domain were investigated by the time-resolved transient grating method. Only a minor conformational change of the BlrP1-BLUF domain was observed.