Veterinary Clinics of North America. Food Animal Practice

The details of all steps involved in the quantification of
biofilm formation in microtiter plates are described. The
presented protocol incorporates information on assessment of
biofilm production by staphylococci, gained both by direct
experience as well as by analysis of methods for assaying
biofilm production. The obtained results should simplify
quantification of biofilm formation in microtiter plates, and
make it more reliable and comparable among different
laboratories.

Quantification of biofilm in microtiter plates: overview oftesting conditions and practical recommendations for assessmentof biofilm production by staphylococci.

Progress in understanding preferential detection of live cells using viability dyes in combination with DNA amplification.

Nucleic acid-based analytical methods, ranging from species-targeted PCRs to metagenomics, have greatly expanded our understanding of microbiological diversity in natural samples. However, these methods provide only limited information on the activities and physiological states of microorganisms in samples. Even the most fundamental physiological state, viability, cannot be assessed cross-sectionally by standard DNA-targeted methods such as PCR. New PCR-based strategies, collectively called molecular viability analyses, have been developed that differentiate nucleic acids associated with viable cells from those associated with inactivated cells. In order to maximize the utility of these methods and to correctly interpret results, it is necessary to consider the physiological diversity of life and death in the microbial world. This article reviews molecular viability analysis in that context and discusses future opportunities for these strategies in genetic, metagenomic, and single-cell microbiology.

Dead or Alive: Molecular Assessment of Microbial Viability

Enhancing the nutritional and health value of beef lipids and their relationship with meat quality

Use of propidium monoazide and quantitative PCR for differentiation of viable Escherichia coli from E. coli killed by mild or pasteurizing heat treatments.

Enhanced control of microbiological contamination of product at a large beef packing plant.

https://era.library.ualberta.ca/items/c139b148-3651-4614-a7ac-c2a7bd7f1d31/view/29754a6d-9fa2-4bf6-b662-3c520ceb5d46/Food%20Microbiol%20%2064%2096%20to%20103.pdf

The locus of heat resistance (LHR) mediates heat resistance in Salmonella enterica, Escherichia coli and Enterobacter cloacae.

An NADH oxidase from the anaerobic hyperthermophilic bacterium Thermotoga maritima was purified. The enzyme was very active in catalyzing the reduction of oxygen to hydrogen peroxide with an optimal pH value of 7 at 80°C. The Vmax was 230 ± 14 μmol/min/mg (kcat/Km = 548,000 min−1 mM−1), and the Km values for NADH and oxygen were 42 ± 3 and 43 ± 4 μM, respectively. The NADH oxidase was a heterodimeric flavoprotein with two subunits with molecular masses of 54 kDa and 46 kDa. Its gene sequences were identified, and the enzyme might represent a new type of NADH oxidase in anaerobes. An NADH-dependent peroxidase with a specific activity of 0.1 U/mg was also present in the cell extract of T. maritima.

Xianqin Yang

Papers

Use of propidium monoazide and quantitative PCR for differentiation of viable Escherichia coli from E. coli killed by mild or pasteurizing heat treatments.

Enhanced control of microbiological contamination of product at a large beef packing plant.

The locus of heat resistance (LHR) mediates heat resistance in Salmonella enterica, Escherichia coli and Enterobacter cloacae.

Characterization of an Exceedingly Active NADH Oxidase from the Anaerobic Hyperthermophilic Bacterium Thermotoga maritima

Substrate utilization by Clostridium estertheticum cultivated in meat juice medium.