Description

Salmonella spp. are members of the family Enterobacteriaceae. They are Gram-negative, facultatively anaerobic, flagellated, rod-shaped organisms. They are approximately 0.7 to 1.5 µm in diameter and 2 to 5 µm in length and responsible for a large number of cases of foodborne illness throughout the world. Salmonella have circular DNA genomes with a mean length of approximately 4530 kb, although this can vary by up 1000 kb. Salmonella classification is extremely complex, however, the genus is divided into two species: S. enterica and S.bongori. S. enterica is then itself divided into 6 biochemically distinct subspecies and the Salmonella genus is further classified into serovars (serotypes) based on the lipopolysaccharide (O), flagella protein (H), and sometimes the capsular (VI) antigens. There are more than 2500 known serovars and within a serovar there may be strains that differ in virulence.

Salmonella are mainly transmitted by the faecal-oral route. They are carried asymptomatically in the intestines or gall bladder of many animals, being continuously or intermittently shed in the faeces. Humans can become infected if they do not wash their hands after contact with infected animals or animal faeces. In such instances the bacteria adhere to and enter the cells of the intestinal epithelium. The toxins produced by the bacteria can damage and kill the cells that line the intestines, which results in intestinal fluid loss. The bacteria can survive for weeks in a dry environment and far longer in water thus they are frequently present in polluted waters. Salmonella can also be carried latently in the mesenteric lymph nodes or tonsils; these bacteria are not shed, but can become reactivated after stress or immunosuppression. In addition, fomites and vectors can spread Salmonella and vertical transmission occurs in birds, with contamination of the vitalize membrane, albumen and possibly the yolk of eggs. Salmonella spp. can also be transmitted in utero in mammals.

There are two different disease conditions that are distinct to salmonellosis; gastroenteritis and enteric typhoid fever. The gastroenteritis is a nonsystemic infection of the intestinal tract and regional lymph nodes that gives rise to headache, muscle aches, diarrhoea, vomiting, abdominal cramping, chills, fever, nausea and dehydration. In contrast, the enteric typhoid fever is a systemic disease in which the microorganism replicates within the cells of the reticuloendothelial system. The symptoms usually appear 6 to 72 hours after ingesting contaminated food although individuals can be infected with the bacteria without having symptoms. Those with and without symptoms shed the bacteria in their stool and it is important that personal hygiene be maintained at all times.

Exceptional value for money
Rapid detection of all clinically relevant subtypes
Positive copy number standard curve for quantification
Highly specific detection profile
High priming efficiency
Broad dynamic detection range (>6 logs)
Sensitive to < 100 copies of target Accurate controls to confirm findings

Introduction

This product provides an easy-to-use workflow for selective isolation of bacterial DNA from samples that are intrinsically rich in host DNA, such as body fluids or swabs. The method is specific for the identification of intact bacteria so it prevents false results due to nucleic acids from dead bacteria. The Kit allows isolation of enriched bacterial DNA suitable for a variety of applications, including qPCR and whole metagenome or 16S rRNA gene sequencing.

Details

Specifications

Principle

This product is based on silica Column purification. This product efficiently depletes human and animal host DNA and yields enriched bacterial DNA. An optimized combination of mechanical and chemical lysis allows efficient disruption of bacterial cells. Target DNA is adsorbed on the membrane, while protein is not adsorbed and is removed with filtration. After washing proteins and other impurities, nucleic acid was finally eluted with low-salt buffer (10mm Tris, pH9.0, 0.5mm EDTA).

Advantages

• High concentration – the host DNA is digested by dnase, without contamination of host DNA
• High recovery – DNA can be recovered at the level of PG
• Good repeatability – silica technology can obtain ideal results every time
• Wide applicability – it can be used in blood, tissue, intestinal contents and other samples

Kit Contents

Storage and Stability

DNase I and Proteinase K should be stored at 2–8°C upon arrival. However, short-term storage (up to 12 weeks) at room temperature (15–25°C) does not affect their performance. The remaining kit components can be stored dry at room temperature (15–25°C) and are stable for at least 18 months under these conditions. The entire kit can be stored at 2–8°C, but in this case buffers should be redissolved before use. Make sure that all buffers are at room temperature when used.

This product provides an easy-to-use workflow for selective isolation of bacterial DNA from samples that are intrinsically rich in host DNA, such as body fluids or swabs. The method is specific for the identification of intact bacteria so it prevents false results due to nucleic acids from dead bacteria. The Kit allows isolation of enriched bacterial DNA suitable for a variety of applications, including qPCR and whole metagenome or 16S rRNA gene sequencing.

Overview

• Ready-to-use
• Quantitative
• Highly Stable
• Precise
• Fourteen discrete fragments ranging from 25 bp to 650 bp in 50 bp increments
• Double intensity reference bands at 200 bp and 400 bp

The Norgen MiniSizer 50 bp DNA Ladder is prepared to ensure quality and batch-to-batch consistency. This Ladder contains fourteen discrete fragments ranging from 25 bp to 650 bp in 50 bp increments with double intensity reference bands at 200 bp and 400 bp. The MiniSizer is ideal for PCR product size confirmation.

Contents:

1mL of premixed DNA ladder (0.5µg/10µL) in loading buffer (10mM EDTA, 10% glycerol, 0.015% bromophenol blue, and 0.17% SDS).

Details

Supporting Data

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MiniSizer 50 bp DNA Ladder (Cat# 11200) – 100 loads

Ladder Properties:
• Fourteen discrete bands, ranging from 50 bp to 650 bp
• Higher intensity bands at 200 bp and 400 bp for easy reference

Recommended Use:

Mix thoroughly. For best results, load 10µL of DNA ladder per well. For precise mass determination with a densitometer, stain gel after electrophoresis using 0.5µg/mL ethidium bromide for 30-40 minutes. The table above shows the size and mass for each band based on 10µL ladder per well.

Storage: 

Stable at room temperature. For longer term storage, -20°C is recommended.

This ladder was standardized using 10µL of DNA per lane on a 0.8 cm thick, 13 x 15 cm, 1.0% agarose gel run in TAE buffer.