Development and validation of a one-tube, nested real-time PCR method suitable for routine detection of Mycobacterium bovis in animal tissue.

Aims: Development and validation of a real-time PCR test for high-throughput routine screening of animal tissue for Mycobacterium bovis and other Mycobacterium tuberculosis complex (MTBC) members.

Methods And Results: A preliminary study compared the results of a combination of five tissue preparation/DNA extraction methods and nine PCR assays on a panel of 92 cattle tissue samples of known M. bovis culture status (55 positive and 37 negative).

Liquid Crystal Devices for Beam Steering Applications.

Liquid crystals are valuable materials for applications in beam steering devices. In this paper, an overview of the use of liquid crystals in the field of adaptive optics specifically for beam steering and lensing devices is presented. The paper introduces the properties of liquid crystals that have made them useful in this field followed by a more detailed discussion of specific liquid crystal devices that act as switchable optical components of refractive and diffractive types.

Multilaboratory Evaluation of a Novel Lateral Flow Immunochromatographic Assay for Confirming Isolation of Mycobacterium bovis from Veterinary Diagnostic Specimens.

A novel lateral flow immunochromatographic device (LFD) was evaluated in several veterinary diagnostic laboratories. It was confirmed to be specific for and cells. The performance of the novel LFD was assessed relative to the confirmatory tests routinely applied after culture (spoligotyping or quantitative PCR [qPCR]) in each laboratory; liquid (MGIT or BacT/Alert) and/or solid (Stonebrink, Coletsos, or Lowenstein-Jensen) cultures were tested.

WhiB7, an Fe-S-dependent transcription factor that activates species-specific repertoires of drug resistance determinants in actinobacteria.

WhiB-like (Wbl) proteins are well known for their diverse roles in actinobacterial morphogenesis, cell division, virulence, primary and secondary metabolism, and intrinsic antibiotic resistance. Gene disruption experiments showed that three different Actinobacteria (Mycobacterium smegmatis, Streptomyces lividans, and Rhodococcus jostii) each exhibited a different whiB7-dependent resistance profile. Heterologous expression of whiB7 genes showed these resistance profiles reflected the host's repertoire of endogenous whiB7-dependent genes.

Mycobacterium tuberculosis modulates its cell surface via an oligopeptide permease (Opp) transport system.

Bacterial species utilize a vast repertoire of surface structures to interact with their surroundings and employ a number of strategies to reconfigure the cellular envelope according to specific stimuli. Gram-positive bacteria, exemplified by Streptomyces and Bacillus species, control production of some exposed molecules by importing oligopeptide signals via permeases (Opp). Such oligopeptides modulate intracellular signaling pathways.

Ribosomally synthesized thiopeptide antibiotics targeting elongation factor Tu.

We identified the thiomuracins, a novel family of thiopeptides produced by a rare-actinomycete bacterium typed as a Nonomuraea species, via a screen for inhibition of growth of the bacterial pathogen Staphylococcus aureus. Thiopeptides are a class of macrocyclic, highly modified peptides that are decorated by thiazoles and defined by a central six-membered heterocyclic ring system. Mining the genomes of thiopeptide-producing strains revealed the elusive biosynthetic route for this class of antibiotics.

Ancestral antibiotic resistance in Mycobacterium tuberculosis.

Chemotherapeutic options to treat tuberculosis are severely restricted by the intrinsic resistance of Mycobacterium tuberculosis to the majority of clinically applied antibiotics. Such resistance is partially provided by the low permeability of their unique cell envelope. Here we describe a complementary system that coordinates resistance to drugs that have penetrated the envelope, allowing mycobacteria to tolerate diverse classes of antibiotics that inhibit cytoplasmic targets.