To accelerate differentiation between Staphylococcus aureus and Coagulase Negative Staphylococci (CNS), this study aimed to compare six different DNA extraction methods from 2 commonly used blood culture materials, i.e. BACTEC and Bact/ALERT. Furthermore, we analyzed the effect of reduced blood culture times for detection of Staphylococci directly from blood culture material. A real-time PCR duplex assay was used to compare 6 different DNA isolation protocols on two different blood culture systems. Negative blood culture material was spiked with MRSA. Bacterial DNA was isolated with: automated extractor EasyMAG (3 protocols), automated extractor MagNA Pure LC (LC Microbiology Kit MGrade), a manual kit MolYsis Plus, and a combination between MolYsis Plus and the EasyMAG. The most optimal isolation method was used to evaluate reduced bacterial culture times. Bacterial DNA isolation with the MolYsis Plus kit in combination with the specific B protocol on the EasyMAG resulted in the most sensitive detection of S.aureus, with a detection limit of 10 CFU/ml, in Bact/ALERT material, whereas using BACTEC resulted in a detection limit of 100 CFU/ml. An initial S.aureus load of 1 CFU/ml blood can be detected after 5 hours of culture in Bact/ALERT3D by combining the sensitive isolation method and the tuf LightCycler assay.
DOCUMENT
Inoculation of maize silage with Lactobacillus buchneri (5 × 105 c.f.u. g-1 of maize silage) prior to ensiling results in the formation of aerobically stable silage. After 9 months, lactic acid bacterium counts are approximately 1010 c.f.u. g-1 in these treated silages. An important subpopulation (5.9 × 107 c.f.u. g-1) is able to degrade 1,2-propanediol, a fermentation product of L. buchneri, under anoxic conditions to 1-propanol and propionic acid. From this group of 1,2-propanediol-fermenting, facultatively anaerobic, heterofermentative lactobacilli, two rod-shaped isolates were purified and characterized. Comparative 16S rDNA sequence analysis revealed that the newly isolated bacteria have identical 16S rDNA sequences and belong phylogenetically to the L. buchneri group. DNA-DNA hybridizations, whole-cell protein fingerprinting and examination of phenotypic properties indicated that these two isolates represent a novel species, for which the name Lactobacillus diolivorans sp. nov. is proposed. The type strain is LMG 19667T ( = DSM 14421T).
DOCUMENT
Summary: Xpaths is a collection of algorithms that allow for the prediction of compound-induced molecular mechanisms of action by integrating phenotypic endpoints of different species; and proposes follow-up tests for model organisms to validate these pathway predictions. The Xpaths algorithms are applied to predict developmental and reproductive toxicity (DART) and implemented into an in silico platform, called DARTpaths.
DOCUMENT
