The Rip1 protease of Mycobacterium tuberculosis controls the SigD regulon.

Regulated intramembrane proteolysis of membrane-embedded substrates by site-2 proteases (S2Ps) is a widespread mechanism of transmembrane signal transduction in bacteria and bacterial pathogens. We previously demonstrated that the Mycobacterium tuberculosis S2P Rip1 is required for full virulence in the mouse model of infection. Rip1 controls transcription in part through proteolysis of three transmembrane anti-sigma factors, anti-SigK, -L, and -M, but there are also Rip1-dependent, SigKLM-independent pathways.

M. tuberculosis intramembrane protease Rip1 controls transcription through three anti-sigma factor substrates.

Regulated intramembrane proteolysis (RIP) is a mechanism of transmembrane signal transduction that functions through intramembrane proteolysis of substrates. We previously reported that the RIP metalloprotease Rv2869c (Rip1) is a determinant of Mycobacterium tuberculosis (Mtb) cell envelope composition and virulence, but the substrates of Rip1 were undefined. Here we show that Rip1 cleaves three transmembrane anti-sigma factors: anti-SigK, anti-SigL and anti-SigM, negative regulators of Sigma K, L and M.

Defining the roles of the periplasmic chaperones SurA, Skp, and DegP in Escherichia coli.

Integral beta-barrel proteins (OMPs) are a major class of outer membrane proteins in Gram-negative bacteria. In Escherichia coli, these proteins are synthesized in the cytoplasm, translocated across the inner membrane via the Sec machinery, and assembled in the outer membrane through an unknown mechanism that requires the outer membrane YaeT complex and the periplasmic chaperones SurA, DegP, and Skp. Here, we have established the relationship between these three chaperones providing insight into the mechanism of OMP biogenesis using depletion analysis.

Lipoprotein SmpA is a component of the YaeT complex that assembles outer membrane proteins in Escherichia coli.

A major role of the outer membrane (OM) of Gram-negative bacteria is to provide a protective permeability barrier for the cell, and proper maintenance of the OM is required for cellular viability. OM biogenesis requires the coordinated assembly of constituent lipids and proteins via dedicated OM assembly machineries. We have previously shown that, in Escherichia coli, the multicomponent YaeT complex is responsible for the assembly of OM beta-barrel proteins (OMPs).

YfiO stabilizes the YaeT complex and is essential for outer membrane protein assembly in Escherichia coli.

Recent advances in the study of bacterial membranes have led to the identification of a multicomponent YaeT complex in the outer membrane (OM) of Gram-negative bacteria that is involved in the targeting and folding of beta-barrel outer membrane proteins (OMPs). In Escherichia coli, this complex consists of an essential OMP, YaeT, and three OM lipoproteins, YfgL, NlpB and YfiO. YfiO is the only essential lipoprotein component of the complex.

Development of novel assays for proteolytic enzymes using rhodamine-based fluorogenic substrates.

Components within synthetic chemical and natural product extract libraries often interfere with fluorescence-based assays. Fluorescence interference can result when the intrinsic spectral properties of colored compounds overlap with the fluorescent probes. Typically, fluorescence-based protease assays use peptide amidomethylcoumarin derivatives as substrates.

Age-Related Differences in Predictors of Adherence to Rehabilitation After Anterior Cruciate Ligament Reconstruction.

OBJECTIVE: To examine whether the relationships between psychological factors and rehabilitation adherence after knee surgery differ as a function of age. DESIGN AND SETTING: Participants completed inventories of self-motivation, social support, athletic identity, and psychological distress before anterior cruciate ligament (ACL) reconstruction. After surgery, participants recorded their completion of home rehabilitation exercises and cryotherapy, and the sport rehabilitation professionals providing their treatment reported on the patients' attendance at, and adherence during, rehabilitation sessions.

Characterization of cluster N5 as a fast-relaxing [4Fe-4S] cluster in the Nqo3 subunit of the proton-translocating NADH-ubiquinone oxidoreductase from Paracoccus denitrificans.

The NADH-quinone oxidoreductase from Paracoccus denitrificans consists of 14 subunits (Nqo1-14) and contains one FMN and eight iron-sulfur clusters. The Nqo3 subunit possesses fully conserved 11 Cys and 1 His in its N-terminal region and is considered to harbor three iron-sulfur clusters; however, only one binuclear (N1b) and one tetranuclear (N4) were previously identified. In this study, the Nqo3 subunit containing 1x[2Fe-2S] and 2x[4Fe-4S] clusters was expressed in Escherichia coli.

Intravenous regional anesthesia with clonidine in the management of complex regional pain syndrome of the knee.

Study Objective: To evaluate the safety and efficacy of administering intravenous regional anesthesia (IVRA) with clonidine in the management of complex regional pain syndrome (CRPS) of the knee.

Design: Prospective, non-blinded study.

Setting: University-affiliated pain management center.

The preemptive analgesic effect of rofecoxib after ambulatory arthroscopic knee surgery.

Unlabelled: Nonsteroidal antiinflammatory drugs (NSAIDs) provide effective postoperative analgesia after arthroscopic knee surgery. Some investigators have suggested that the preemptive administration of NSAIDs may reduce postoperative analgesic requirements and hypersensitivity. We evaluated the analgesic effect of administering rofecoxib either before or after surgical incision in patients undergoing arthroscopic knee surgery under local anesthesia.