Takanori Hirano

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BACKGROUND The green-fluorescent protein (GFP) of the jellyfish Aequorea victoria has recently been used as a universal reporter in a broad range of heterologous living cells and organisms. Although successful in some plant transient expression assays based on strong promoters or high copy number viral vectors, further improvement of expression efficiency(More)
FlhB, an integral membrane protein, gates the type III flagellar export pathway of Salmonella. It permits export of rod/hook-type proteins before hook completion, whereupon it switches specificity to recognize filament-type proteins. The cytoplasmic C-terminal domain of FlhB (FlhBC) is cleaved between Asn-269 and Pro-270, defining two subdomains: FlhBCN and(More)
Bacterial flagella contain a specialized secretion apparatus that functions to deliver the protein subunits that form the filament and other structures to outside the membrane. This apparatus is related to the injectisome used by many gram-negative pathogens and symbionts to transfer effector proteins into host cells; in both systems this export mechanism(More)
The 5'-untranslated region (5'UTR) of the fliC flagellin gene of Salmonella contains sequences critical for efficient fliC mRNA translation coupled to assembly. In a previous study we used targeted mutagenesis of the 5' end of the fliC gene to isolate single base changes defective in fliC gene translation. This identified a predicted stem-loop structure,(More)
Interspecies signalling between Porphyromonas gingivalis and Streptococcus gordonii serves to constrain development of dual species communities. Contact with S. gordonii propagates a tyrosine phosphorylation-dependent signal within P. gingivalis that culminates in reduced transcription of adhesin and signalling genes. Here we demonstrate the involvement of(More)
Porphyromonas gingivalis is a major pathogen in severe and chronic manifestations of periodontal disease, which is one of the most common infections of humans. A central feature of P. gingivalis pathogenicity is dysregulation of innate immunity at the gingival epithelial interface, including suppression of IL-8 production by epithelial cells. NF-kB is a(More)
Most flagellar proteins of Salmonella are exported to their assembly destination via a specialized apparatus. This apparatus is a member of the type III superfamily, which is widely used for secretion of virulence factors by pathogenic bacteria. Extensive studies have been carried out on the export of several of the flagellar proteins, most notably the hook(More)
A molecular ruler, FliK, controls the length of the flagellar hook. FliK measures hook length and catalyses the secretion-substrate specificity switch from rod-hook substrate specificity to late substrate secretion, which includes the filament subunits. Here, we show normal hook-length control and filament assembly in the complete absence of the C-ring thus(More)
The rod component of the bacterial flagellum polymerizes from the inner membrane across the periplasmic space and stops at a length of 25 nm at the outer membrane. Bushing structures, the P- and L-rings, polymerize around the distal rod and form a pore in the outer membrane. The flagellar hook structure is then added to the distal rod growing outside the(More)
Interspecies communication between Porphyromonas gingivalis and Streptococcus gordonii underlies the development of synergistic dual species communities. Contact with S. gordonii initiates signal transduction within P. gingivalis that is based on protein tyrosine (de)phosphorylation. In this study, we characterize a bacterial tyrosine (BY) kinase(More)