Design, synthesis, and in vitro biological evaluation of meta-sulfonamidobenzamide-based antibacterial LpxH inhibitors.

New antibacterial compounds are urgently needed, especially for infections caused by the top-priority Gram-negative bacteria that are increasingly difficult to treat. Lipid A is a key component of the Gram-negative outer membrane and the LpxH enzyme plays an important role in its biosynthesis, making it a promising antibacterial target. Inspired by previously reported ortho-N-methyl-sulfonamidobenzamide-based LpxH inhibitors, novel benzamide substitutions were explored in this work to assess their in vitro activity.

Antibiotic class with potent in vivo activity targeting lipopolysaccharide synthesis in Gram-negative bacteria.

Here, we describe the identification of an antibiotic class acting via LpxH, a clinically unexploited target in lipopolysaccharide synthesis. The lipopolysaccharide synthesis pathway is essential in most Gram-negative bacteria and there is no analogous pathway in humans. Based on a series of phenotypic screens, we identified a hit targeting this pathway that had activity on efflux-defective strains of .

Does the external remote controller's reading correspond to the actual lengthening in magnetic-controlled growing rods?

Purpose: Magnetic-controlled growing rods (MCGRs) are now routinely used in many centres to treat early-onset scoliosis (EOS). MCGR lengthening is done non-invasively by the external remote controller (ERC). Our experience suggests that there may be a discrepancy between the reported rod lengthening on the ERC and the actual rod lengthening.

Targeting an Aromatic Hotspot in Plasmodium falciparum 1-Deoxy-d-xylulose-5-phosphate Reductoisomerase with β-Arylpropyl Analogues of Fosmidomycin.

Blocking the 2-C-methyl-d-erythrithol-4-phosphate pathway for isoprenoid biosynthesis offers new ways to inhibit the growth of Plasmodium spp. Fosmidomycin [(3-(N-hydroxyformamido)propyl)phosphonic acid, 1] and its acetyl homologue FR-900098 [(3-(N-hydroxyacetamido)propyl)phosphonic acid, 2] potently inhibit 1-deoxy-d-xylulose-5-phosphate reductoisomerase (Dxr), a key enzyme in this biosynthetic pathway. Arylpropyl substituents were introduced at the β-position of the hydroxamate analogue of 2 to study changes in lipophilicity, as well as electronic and steric properties.

Do magnetic growing rods have lower complication rates compared with conventional growing rods?

Background Context: The main advantage cited for the use of the magnetic controlled growing rod (MCGR) system over the conventional growing rod (CGR) in early-onset scoliosis is avoiding repeated invasive surgical procedures for lengthening, thus reducing, complications.

Purpose: The study aimed to evaluate the complications of the MCGR system against the CGR system in our center.

Study Design/setting: This is a retrospective case control series.

Magnetic controlled growing rods for early-onset scoliosis: a 4-year follow-up.

Background Context: There have been no studies with medium-term follow-up of magnetic controlled growing rods (MCGRs).

Purpose: This study aimed to report our single center experience of a magnetic growing rod system with an average of 4 years' follow-up.

Study Design/setting: A retrospective case series was carried out.

Synthesis and bioactivity of β-substituted fosmidomycin analogues targeting 1-deoxy-D-xylulose-5-phosphate reductoisomerase.

Blocking the 2-C-methyl-d-erythrithol-4-phosphate (MEP) pathway for isoprenoid biosynthesis offers interesting prospects for inhibiting Plasmodium or Mycobacterium spp. growth. Fosmidomycin (1) and its homologue FR900098 (2) potently inhibit 1-deoxy-d-xylulose-5-phosphate reductoisomerase (Dxr), a key enzyme in this pathway.

Assessment of Mycobacterium tuberculosis pantothenate kinase vulnerability through target knockdown and mechanistically diverse inhibitors.

Pantothenate kinase (PanK) catalyzes the phosphorylation of pantothenate, the first committed and rate-limiting step toward coenzyme A (CoA) biosynthesis. In our earlier reports, we had established that the type I isoform encoded by the coaA gene is an essential pantothenate kinase in Mycobacterium tuberculosis, and this vital information was then exploited to screen large libraries for identification of mechanistically different classes of PanK inhibitors. The present report summarizes the synthesis and expansion efforts to understand the structure-activity relationships leading to the optimization of enzyme inhibition along with antimycobacterial activity.

DXR inhibition by potent mono- and disubstituted fosmidomycin analogues.

The antimalarial compound fosmidomycin targets DXR, the enzyme that catalyzes the first committed step in the MEP pathway, producing the essential isoprenoid precursors, isopentenyl diphosphate and dimethylallyl diphosphate. The MEP pathway is used by a number of pathogens, including Mycobacterium tuberculosis and apicomplexan parasites, and differs from the classical mevalonate pathway that is essential in humans. Using a structure-based approach, we designed a number of analogues of fosmidomycin, including a series that are substituted in both the Cα and the hydroxamate positions.

Structural and biochemical characterization of compounds inhibiting Mycobacterium tuberculosis pantothenate kinase.

Mycobacterium tuberculosis, the bacterial causative agent of tuberculosis, currently affects millions of people. The emergence of drug-resistant strains makes development of new antibiotics targeting the bacterium a global health priority. Pantothenate kinase, a key enzyme in the universal biosynthesis of the essential cofactor CoA, was targeted in this study to find new tuberculosis drugs.

Structure and function of the transketolase from Mycobacterium tuberculosis and comparison with the human enzyme.

The transketolase (TKT) enzyme in Mycobacterium tuberculosis represents a novel drug target for tuberculosis treatment and has low homology with the orthologous human enzyme. Here, we report on the structural and kinetic characterization of the transketolase from M. tuberculosis (TBTKT), a homodimer whose monomers each comprise 700 amino acids.

Structural studies on Mycobacterium tuberculosis DXR in complex with the antibiotic FR-900098.

A number of pathogens, including the causative agents of tuberculosis and malaria, synthesize the essential isoprenoid precursor isopentenyl diphosphate via the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway rather than the classical mevalonate pathway that is found in humans. As part of a structure-based drug-discovery program against tuberculosis, DXR, the enzyme that carries out the second step in the MEP pathway, has been investigated. This enzyme is the target for the antibiotic fosmidomycin and its active acetyl derivative FR-900098.

Design, synthesis, and X-ray crystallographic studies of α-aryl substituted fosmidomycin analogues as inhibitors of Mycobacterium tuberculosis 1-deoxy-D-xylulose 5-phosphate reductoisomerase.

The natural antibiotic fosmidomycin acts via inhibition of 1-deoxy-d-xylulose 5-phosphate reductoisomerase (DXR), an essential enzyme in the non-mevalonate pathway of isoprenoid biosynthesis. Fosmidomycin is active on Mycobacterium tuberculosis DXR (MtDXR), but it lacks antibacterial activity probably because of poor uptake. α-Aryl substituted fosmidomycin analogues have more favorable physicochemical properties and are also more active in inhibiting malaria parasite growth.

Structural and functional studies of mycobacterial IspD enzymes.

A number of pathogens, including the causative agents of tuberculosis and malaria, synthesize isopentenyl diphosphate via the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway rather than the classical mevalonate pathway found in humans. As part of a structure-based drug-discovery program against tuberculosis, IspD, the enzyme that carries out the third step in the MEP pathway, was targeted. Constructs of both the Mycobacterium smegmatis and the Mycobacterium tuberculosis enzymes that were suitable for structural and inhibitor-screening studies were engineered.

Practical application of bioinformatics by the multidisciplinary VIZIER consortium.

This review focuses on bioinformatics technologies employed by the EU-sponsored multidisciplinary VIZIER consortium (Comparative Structural Genomics of Viral Enzymes Involved in Replication, FP6 PROJECT: 2004-511960, active from 1 November 2004 to 30 April 2009), to achieve its goals. From the management of the information flow of the project, to bioinformatics-mediated selection of RNA viruses and prediction of protein targets, to the analysis of 3D protein structures and antiviral compounds, these technologies provided a communication framework and integrated solutions for steady and timely advancement of the project. RNA viruses form a large class of major pathogens that affect humans and domestic animals.

Carbonic anhydrase inhibitors. Characterization and inhibition studies of the most active beta-carbonic anhydrase from Mycobacterium tuberculosis, Rv3588c.

The Rv3588c gene product of Mycobacterium tuberculosis, a beta-carbonic anhydrase (CA, EC 4.2.1.

Recurrence of kyphosis and its functional implications after surgical stabilization of dorsolumbar unstable burst fractures.

Background Context: Treatment of unstable burst fractures in the dorsolumbar spine still remains controversial. Surgical stabilization has been aimed to prevent long-term back pain and progression of deformity.

Purpose: This study was aimed to analyze the degree of loss of correction of the angle of kyphosis with pedicle screw instrumentation in place and the components responsible for the recurrence of kyphosis after surgical stabilization of dorsolumbar A3 fractures and to assess the return of functional capacity in these patients.

Structural basis for the inhibition of Mycobacterium tuberculosis glutamine synthetase by novel ATP-competitive inhibitors.

Glutamine synthetase (GS, EC 6.3.1.

Structure of the methyltransferase domain from the Modoc virus, a flavivirus with no known vector.

The Modoc virus (MODV) is a flavivirus with no known vector (NKV). Evolutionary studies have shown that the viruses in the MODV group have evolved in association with mammals (bats, rodents) without transmission by an arthropod vector. MODV methyltransferase is the first enzyme from this evolutionary branch to be structurally characterized.

Crystallization of Mycobacterium smegmatis methionyl-tRNA synthetase in the presence of methionine and adenosine.

Methionyl-tRNA synthetase (MetRS) from Mycobacterium smegmatis was recombinantly expressed in Escherichia coli and purified using Ni(2+)-affinity and size-exclusion chromatography. Crystals formed readily in the presence of the ligands methionine and adenosine. These two ligands are components of an intermediate in the two-step catalytic mechanism of MetRS.

Structural, biochemical, and in vivo investigations of the threonine synthase from Mycobacterium tuberculosis.

Threonine biosynthesis is a general feature of prokaryotes, eukaryotic microorganisms, and higher plants. Since mammals lack the appropriate synthetic machinery, instead obtaining the amino acid through their diet, the pathway is a potential focus for the development of novel antibiotics, antifungal agents, and herbicides. Threonine synthase (TS), a pyridoxal-5-phosphate-dependent enzyme, catalyzes the final step in the pathway, in which L-homoserine phosphate and water are converted into threonine and inorganic phosphate.

Data management in structural genomics: an overview.

Data management has been identified as a crucial issue in all large-scale experimental projects. In this type of project, many different persons manipulate multiple objects in different locations; thus, unless complete and accurate records are maintained, it is extremely difficult to understand exactly what has been done, when it was done, who did it, and what exact protocol was used. All of this information is essential for use in publications, reusing successful protocols, determining why a target has failed, and validating and optimizing protocols.