Listeria monocytogenes, a food-borne pathogen, has the capacity to maintain intracellular pH (pHi) homeostasis in acidic environments, but the underlying mechanisms remain elusive. Here, we report a simple microplate-based fluorescent method to determine pHi of listerial cells that were prelabeled with the fluorescent dye carboxyfluorescein diacetate N-succinimidyl ester and subjected to acid s...

We identified and quantified abundant iron-oxidizing bacteria (FeOB) at three iron-rich, metal-contaminated creek sites with increasing sediment pH from extremely acidic (R1, pH 2.7), to moderately acidic (R2, pH 4.4), to slightly acidic (R3, pH 6.3) in a former uranium-mining district. The geochemical parameters showed little variations over the 1.5 year study period. The highest metal concent...

To evaluate the effect of yield stress on hydrogen embrittlement (HE) martensitic and ferritic steels, (H) capture by structural inhomogeneities (hydrogen traps) plastic deformation mechanism corrosion cracking (SCC) are considered. In presence hydrogen, brittle fracture high-strength steels consists flat areas intergranular at initial austenitic grain boundaries quasi-brittle cracks martensite...

Objectives: Periodontal pathogens need acidic environments to proliferate in periodontium, and their growth is affected by the salivary flow rate and pH of the mouth. Alterations in flow and acidity of saliva have an important effect on oral diseases such as periodontitis. This study was designed to compare salivary pH and flow rate before and after using green tea, black tea and coffee in pati...

Acidithiobacillus ferrivorans SS3 is a psychrotolerant acidophile capable of growth in the range of 5° to 30°C (optimum, ≈25°C). It gains energy from the oxidation of ferrous iron and inorganic sulfur compounds and obtains organic carbon from carbon dioxide. Here, we present the draft genome sequence of A. ferrivorans SS3 that will permit investigation of genes involved in growth in acidic envi...

Patients with recently exposed root surfaces may become susceptible to acidic environments, even when other pertinent environmental factors remain unchanged. The inorganic chemical events of the root caries are similar to that of the enamel, however, the permeability and reactivity of the root surface allows the demineralization process to occur at a higher pH than in enamel. Therefore, clinici...

corrosion makes huge economic and ecologic damage all over the world. biologic corrosion of sewer pipes is considered as a serious limitation in economic perspectives. to prevent biologic corrosive damage, lining techniques can be applied by materials and aggregate resistant to attack bacterially in sewer pipes. the role of bacteria is that they convert sulfur compounds into sulfuric acid which...

a simple and mild method for tetrahydropyranylation of alcohols is reported at room temperature using a catalytic amount of 3-methylimidazolinium hydrogensulfate([hmim]hso4) as a green, efficient and reusable catalyst. using solvent-free conditions, non-toxic and inexpensive materials, modest and clean work-up, short reaction times and high yields of the products are the advantages of this method.