Elucidation of critical chemical moieties of metallo-β-lactamase inhibitors and prioritisation of target metallo-β-lactamases.

The urgent demand for effective countermeasures against metallo-β-lactamases (MBLs) necessitates development of novel metallo-β-lactamase inhibitors (MBLIs). This study is dedicated to identifying critical chemical moieties within previously developed MBLIs, and critical MBLs should serve as the target in MBLI evaluations. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), a systematic literature analysis was conducted, and the NCBI RefSeq genome database was exploited to access the abundance profile and taxonomic distribution of MBLs and their variant types.

Prioritization of Critical Factors for Surveillance of the Dissemination of Antibiotic Resistance in : A Systematic Review.

is the primary opportunistic human pathogen responsible for a range of acute and chronic infections; it poses a significant threat to immunocompromised patients and is the leading cause of morbidity and mortality for nosocomial infections. Its high resistance to a diverse array of antimicrobial agents presents an urgent health concern. Among the mechanisms contributing to resistance in , the horizontal acquisition of antibiotic resistance genes (ARGs) via mobile genetic elements (MGEs) has gained recognition as a substantial concern in clinical settings, thus indicating that a comprehensive understanding of ARG dissemination within the species is strongly required for surveillance.

Identification of the inhibitory mechanism of ecumicin and rufomycin 4-7 on the proteolytic activity of Mycobacterium tuberculosis ClpC1/ClpP1/ClpP2 complex.

Ecumicin and rufomycin 4-7 disrupt protein homeostasis in Mycobacterium tuberculosis by inhibiting the proteolytic activity of the ClpC1/ClpP1/ClpP2 complex. Although these compounds target ClpC1, their effects on the ATPase activity of ClpC1 and proteolytic activity of ClpC1/ClpP1/ClpP2 vary. Herein, we explored the ClpC1 molecular dynamics with these compounds through fluorescence correlation spectroscopy.

Potential Benefits of Allogeneic Haploidentical Adipose Tissue-Derived Stromal Vascular Fraction in a Hutchinson-Gilford Progeria Syndrome Patient.

Hutchinson-Gilford progeria syndrome (HGPS) is a rare, fatal, and genetic disorder in the gene encoding for prelamin A. Normally, prelamin A is processed to become lamin A protein. In HGPS patients, there is a heterozygous mutation in gene, in which there is a deletion of genetic codes responsible for 50 amino acids at the C-terminus of prelamin A.

Clinical Protocol of Producing Adipose Tissue-Derived Stromal Vascular Fraction for Potential Cartilage Regeneration.

Osteoarthritis (OA) is one of the most common debilitating disorders. Recently, numerous attempts have been made to improve the functions of the knees by using different forms of mesenchymal stem cells (MSCs). In Korea, bone marrow concentrates and cord blood-derived stem cells have been approved by the Korean Food and Drug Administration (KFDA) for cartilage regeneration.

Cartilage Regeneration in Humans with Adipose Tissue-Derived Stem Cells and Adipose Stromal Vascular Fraction Cells: Updated Status.

Adipose tissue-derived stem cells (ASCs) in the form of stromal vascular fraction (SVF) and cultured expansion have been applied in clinical settings in some countries to treat osteoarthritis (OA) of knees, one of the most common debilitating, incurable disorders. Since the first report of successful cartilage-like tissue regeneration with autologous adipose SVF containing ASCs, there has been a gradual increase in the number of publications confirming such results. Thus far, most of the reports have been limited to treatments of OA of knees.

Antimicrobial Resistance of Hypervirulent : Epidemiology, Hypervirulence-Associated Determinants, and Resistance Mechanisms.

is one of the most clinically relevant species in immunocompromised individuals responsible for community-acquired and nosocomial infections, including pneumonias, urinary tract infections, bacteremias, and liver abscesses. Since the mid-1980s, hypervirulent , generally associated with the hypermucoviscosity phenotype, has emerged as a clinically significant pathogen responsible for serious disseminated infections, such as pyogenic liver abscesses, osteomyelitis, and endophthalmitis, in a generally younger and healthier population. Hypervirulent infections were primarily found in East Asia and now are increasingly being reported worldwide.

Biochemical Characterization of a Novel GH86 β-Agarase Producing Neoagarohexaose from G7.

A novel β-agarase, AgaJ5, was identified from an agar-degrading marine bacterium, G7. It belongs to the glycoside hydrolase family 86 and is composed of 805 amino acids with a 30-amino-acid signal peptide. Zymogram analysis showed that purified AgaJ5 has agarase activity.

Biology of : Pathogenesis, Antibiotic Resistance Mechanisms, and Prospective Treatment Options.

is undoubtedly one of the most successful pathogens responsible for hospital-acquired nosocomial infections in the modern healthcare system. Due to the prevalence of infections and outbreaks caused by multi-drug resistant , few antibiotics are effective for treating infections caused by this pathogen. To overcome this problem, knowledge of the pathogenesis and antibiotic resistance mechanisms of is important.

Cloning, Expression, and Biochemical Characterization of a Novel Acidic GH16 β-Agarase, AgaJ11, from Gayadomonas joobiniege G7.

A novel β-agarase AgaJ11 belonging to the glycoside hydrolase (GH) 16 family was identified from an agar-degrading bacterium Gayadomonas joobiniege G7. AgaJ11 was composed of 317 amino acids (35 kDa), including a 26-amino acid signal peptide, and had the highest similarity (44 % identity) to a putative β-agarase from an agarolytic marine bacterium Agarivorans albus MKT 106. The agarase activity of purified AgaJ11 was confirmed by zymogram analysis.

Regeneration of Cartilage in Human Knee Osteoarthritis with Autologous Adipose Tissue-Derived Stem Cells and Autologous Extracellular Matrix.

This clinical case series demonstrates that percutaneous injections of autologous adipose tissue-derived stem cells (ADSCs) and homogenized extracellular matrix (ECM) in the form of adipose stromal vascular fraction (SVF), along with hyaluronic acid (HA) and platelet-rich plasma (PRP) activated by calcium chloride, could regenerate cartilage-like tissue in human knee osteoarthritis (OA) patients. Autologous lipoaspirates were obtained from adipose tissue of the abdominal origin. Afterward, the lipoaspirates were minced to homogenize the ECM.

A new in vitro hemagglutinin inhibitor screening system based on a single-vesicle fusion assay.

Hemagglutinin (HA) from the influenza virus plays a pivotal role in the infection of host mammalian cells and is, therefore, a druggable target, similar to neuraminidase. However, research involving the influenza virus must be conducted in facilities certified at or above Biosafety Level 2 because of the potential threat of the contagiousness of this virus. To develop a new HA inhibitor screening system without intact influenza virus, we conceived a single-vesicle fusion assay using full-length recombinant HA.

Global Dissemination of Carbapenemase-Producing Klebsiella pneumoniae: Epidemiology, Genetic Context, Treatment Options, and Detection Methods.

The emergence of carbapenem-resistant Gram-negative pathogens poses a serious threat to public health worldwide. In particular, the increasing prevalence of carbapenem-resistant Klebsiella pneumoniae is a major source of concern. K.

Quantitative proteomic view associated with resistance to clinically important antibiotics in Gram-positive bacteria: a systematic review.

The increase of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) poses a worldwide and serious health threat. Although new antibiotics, such as daptomycin and linezolid, have been developed for the treatment of infections of Gram-positive pathogens, the emergence of daptomycin-resistant and linezolid-resistant strains during therapy has now increased clinical treatment failures. In the past few years, studies using quantitative proteomic methods have provided a considerable progress in understanding antibiotic resistance mechanisms.

Educational effectiveness, target, and content for prudent antibiotic use.

Widespread antimicrobial use and concomitant resistance have led to a significant threat to public health. Because inappropriate use and overuse of antibiotics based on insufficient knowledge are one of the major drivers of antibiotic resistance, education about prudent antibiotic use aimed at both the prescribers and the public is important. This review investigates recent studies on the effect of interventions for promoting prudent antibiotics prescribing.

Structural basis for carbapenem-hydrolyzing mechanisms of carbapenemases conferring antibiotic resistance.

Carbapenems (imipenem, meropenem, biapenem, ertapenem, and doripenem) are β-lactam antimicrobial agents. Because carbapenems have the broadest spectra among all β-lactams and are primarily used to treat infections by multi-resistant Gram-negative bacteria, the emergence and spread of carbapenemases became a major public health concern. Carbapenemases are the most versatile family of β-lactamases that are able to hydrolyze carbapenems and many other β-lactams.

Strategies to minimize antibiotic resistance.

Antibiotic resistance can be reduced by using antibiotics prudently based on guidelines of antimicrobial stewardship programs (ASPs) and various data such as pharmacokinetic (PK) and pharmacodynamic (PD) properties of antibiotics, diagnostic testing, antimicrobial susceptibility testing (AST), clinical response, and effects on the microbiota, as well as by new antibiotic developments. The controlled use of antibiotics in food animals is another cornerstone among efforts to reduce antibiotic resistance. All major resistance-control strategies recommend education for patients, children (e.

Lipid a biosynthesis of multidrug-resistant pathogens - a novel drug target.

The rapid increase of human infections by multidrug-resistant (MDR) Gram-negative pathogens poses a serious health threat and demands the identification of new strategies, molecular targets, and agents for the treatment of Gram-negative bacterial infections. The biosynthesis of lipid A, the membrane-anchoring portion of lipopolysaccharide (LPS), is one promising target for novel antibiotic design because lipid A is essential for LPS assembly in most Gram-negative bacteria. The first three enzymes in the biosynthesis of lipid A, UDP-N-acetylglucosamine acyltransferase (LpxA), UDP-3-O-(R-3-hydroxyacyl)-N-acetylglucosamine deacetylase (LpxC) and UDP- 3-O-(R-3-hydroxyacyl)glucosamine N-acyltransferase (LpxD), have emerged as an attractive Gram-negative antibacterial molecular target.

Crystallization and preliminary diffraction studies of GIM-1, a class B carbapenem-hydrolyzing β-lactamase.

GIM-1 is a member of the class B carbapenemases (metallo-β-lactamases; MBLs) and has a wide spectrum of activity against carbapenems, penicillins and extended-spectrum cephalosporins, but not aztreonam. GIM-1 presents an enormous challenge to infection control, particularly in the eradication of Gram-negative pathogens including Enterobacteriaceae, Pseudomonas aeruginosa, Acinetobacter baumannii and nonfermenters. There are presently few or no drugs in late-stage development for these pathogens and GIM-1 is a potential target for the development of antimicrobial agents against pathogens producing MBLs.

Crystallization and preliminary diffraction studies of SFC-1, a carbapenemase conferring antibiotic resistance.

SFC-1, a class A carbapenemase that confers antibiotic resistance, hydrolyzes the β-lactam rings of β-lactam antibiotics (carbapenems, cephalosporins, penicillins and aztreonam). SFC-1 presents an enormous challenge to infection control, particularly in the eradication of Gram-negative pathogens. As SFC-1 exhibits a remarkably broad substrate range, including β-lactams of all classes, the enzyme is a potential target for the development of antimicrobial agents against pathogens producing carbapenemases.

Determination of pentapeptide repeat units in Qnr proteins by the structure-based alignment approach.

The Qnr proteins belong to the pentapeptide repeat protein family. Despite each pentapeptide repeat unit being an important structural determinant, accurately determining pentapeptide repeat units in the Qnr proteins through sequence-based alignments has been challenging. In the present study, the pentapeptide repeat units of the nine representative Qnr proteins have been precisely determined via the structure-based alignment approach using homology modeling and superposition of their best models.