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<i>Pseudomonas aeruginosa</i> is an opportunistic pathogen that synthesizes and secretes a wide range of virulence factors. <i>P. aeruginosa</i> poses a potential threat to human health worldwide due to its omnipresent nature, robust host accumulation, high virulence, and significant resistance to multiple antibiotics. The pathogenicity of <i>P. aeruginosa</i>, which is associated with acute and chronic infections, is linked with multiple virulence factors and associated secretion systems, such

Eukaryotic translation initiation factor 5A (eIF-5A) is a ubiquitous protein found in all eukaryotic cells. The protein is closely associated with cell proliferation in the G1-S stage of the cell cycle. Recent findings show that the eIF-5A proteins are highly expressed in tumor cells and act as a cofactor of the Rev protein in HIV-1-infected cells. The mature eIF is the only protein known to have the unusual amino acid hypusine, a post-translationally modified lysine. The crystal structure of eI

β-catenin is a key signal transducer in the canonical WNT pathway and is negatively regulated by ubiquitin-dependent proteolysis. Through screening of various deubiquitinating enzymes (DUBs), we identified ubiquitin specific protease 4 (USP4) as a candidate for β-catenin-specific DUB. The effects of USP4 overexpression or knockdown suggested that USP4 positively controls the stability of β-catenin and enhances β-catenin-regulated transcription. Domain mapping results revealed that the C-terminal

In response to fungal invasion and other signals, plants accumulate a number of proteins that are involved in defense against pathogens.1 Among these proteins, pathogenesis-related (PR) proteins are grouped into families based on primary structure, serological relatedness, and enzymatic and biological activities.2 Osmotin is a 24 kDa protein belonging to the PR-5 protein family whose members are homologous to the sweet-tasting protein thaumatin. Osmotin and other PR-5 proteins were shown to have

The receptor activator of nuclear factor-κB (RANK) and its ligand RANKL, which belong to the tumor necrosis factor (TNF) receptor-ligand family, mediate osteoclastogenesis. The crystal structure of the RANKL ectodomain (eRANKL) in complex with the RANK ectodomain (eRANK) combined with biochemical assays of RANK mutants indicated that three RANK loops (Loop1, Loop2, and Loop3) bind to the interface of a trimeric eRANKL. Loop3 is particularly notable in that it is structurally distinctive from oth

Two birds with one stone: When platinum nanoparticles are encapsulated by a bacterial aminopeptidase, the novel hybrid combines platinum-catalyzed hydrogenation and peptidase-catalyzed hydrolysis for multistep synthesis (see picture). This concept of bioinorganic integration can be extended to various enzymes and inorganic materials, allowing for the design and fabrication of novel multifunctional materials. Detailed facts of importance to specialist readers are published as ”Supporting Informat

HtrA (high temperature requirement A), a periplasmic heat-shock protein, functions as a molecular chaperone at low temperatures, and its proteolytic activity is turned on at elevated temperatures. To investigate the mechanism of functional switch to protease, we determined the crystal structure of the NH(2)-terminal protease domain (PD) of HtrA from Thermotoga maritima, which was shown to retain both proteolytic and chaperone-like activities. Three subunits of HtrA PD compose a trimer, and multi

Fos-related-antigen-1 (Fra-1), a member of the activator protein-1 (AP-1) transcription factor superfamily, has an essential role in cancer progress and metastasis and Fra-1 is considered a therapeutic target in metastatic cancer including metastatic colorectal cancer (mCRC). However, its regulation at protein level has not yet been clearly elucidated. We found that ubiquitin-specific protease 21 (USP21) increases Fra-1 stability by deubiquitinating Fra-1 and enhances the expression of Fra-1 tar