A High-Homology Region Provides the Possibility of Detecting β-Barrel Pore-Forming Toxins from Various Bacterial Species.

The pathogenicity of many bacteria, including and , depends on pore-forming toxins (PFTs), which cause the lysis of host cells by forming pores in the membranes of eukaryotic cells. Bioinformatic analysis revealed a region homologous to the Lys171-Gly250 sequence in hemolysin II (HlyII) from in over 600 PFTs, which we designated as a "homologous peptide". Three β-barrel PFTs were used for a detailed comparative analysis.

Region Met225 to Ile412 of Hemolysin II Is Capable to Agglutinate Red Blood Cells.

Hemolysin II (HlyII) is one of the virulence factors of the opportunistic bacterium belonging to the group of β-pore-forming toxins. This work created a genetic construct encoding a large C-terminal fragment of the toxin (HlyIILCTD, M225-I412 according to the numbering of amino acid residues in HlyII). A soluble form of HlyIILCTD was obtained using the SlyD chaperone protein.

Universal and rapid method for purification of GFP-like proteins by the ethanol extraction.

GFP-like fluorescent proteins (FPs) are crucial in biological and biomedical studies. The majority of FP purification techniques either include multiple time-consuming chromatography steps with a low yield of the desired product or require prior protein modification (addition of special tags). In the present work, we propose an alternative ethanol extraction-based technique previously used for GFP purification and then modified for diverse FPs originated from different sources.

Barnase-barstar high affinity interaction phenomenon as the base for the heterogenous bioluminescence pseudorabies virus' immunoassay.

The effective new variant of "sandwich" bioluminescent enzyme immunoassay (BEIA) for the sensitive detection of glycoprotein B (gB) of pseudorabies virus (PrV) was presently developed. The high affinity interaction of barnase-barstar protein pair and photoprotein obelin as bioluminescent marker were for the first time successfully applied to BEIA development. Preliminary the two monoclonal antibodies, 11/5 and 34/2, were raised against gB for ELISA PrV detection.

Traditional GFP-type cyclization and unexpected fragmentation site in a purple chromoprotein from Anemonia sulcata, asFP595.

The purple chromoprotein (asFP595) from Anemonia sulcata belongs to the family of green fluorescent protein (GFP). Absorption and emission spectra of asFP595 are similar to those of a number of recently cloned GFP-like red proteins of the DsRed subfamily. The earlier proposed asFP595 chromophore structure [Martynov, V.

Fusion of Aequorea victoria GFP and aequorin provides their Ca(2+)-induced interaction that results in red shift of GFP absorption and efficient bioluminescence energy transfer.

The bioluminescence emitted by Aequorea victoria jellyfish is greenish while its single bioluminescent photoprotein aequorin emits blue light. This phenomenon may be explained by a bioluminescence resonance energy transfer (BRET) from aequorin chromophore to green fluorescent protein (GFP) co-localized with it. However, a slight overlapping of the aequorin bioluminescence spectrum with the GFP absorption spectrum and the absence of marked interaction between these proteins in vitro pose a question on the mechanism providing the efficient BRET in A.

zFP538, a yellow fluorescent protein from coral, belongs to the DsRed subfamily of GFP-like proteins but possesses the unexpected site of fragmentation.

The yellow fluorescent protein (zFP538) from coral Zoanthus sp. belongs to a family of green fluorescent protein (GFP). Absorption and emission spectra of zFP538 show an intermediate bathochromic shift as compared with a number of recently cloned GFP-like red fluorescent and nonfluorescent chromoproteins of the DsRed subfamily.

Homogeneous assay for biotin based on Aequorea victoria bioluminescence resonance energy transfer system.

Here we describe a homogeneous assay for biotin based on bioluminescence resonance energy transfer (BRET) between aequorin and enhanced green fluorescent protein (EGFP). The fusions of aequorin with streptavidin (SAV) and EGFP with biotin carboxyl carrier protein (BCCP) were purified after expression of the corresponding genes in Escherichia coli cells. Association of SAV-aequorin and BCCP-EGFP fusions was followed by BRET between aequorin (donor) and EGFP (acceptor), resulting in significantly increasing 510 nm and decreasing 470 nm bioluminescence intensity.