Acidothermophilic bacteria of the genus Alicyclobacillus are frequent contaminants of fruit-based products. This study is the first attempt to characterize the physico-chemical surface properties of two Alicyclobacillus sp. and quantify their adhesion disposition to model materials [diethylaminoethyl (DEAE), carboxyl- and octyl-modified magnetic beads] representing materials with different surface properties used in the food industry. An insight into the mechanism of adhesion was gained through comparison of experimental adhesion intensities with predictions of a colloidal interaction model (XDLVO). Experimental data (contact angles, zeta potentials, size) on interacting surfaces (cells and materials) were used as inputs into the XDLVO model. The results revealed that the most significant adhesion occurred at pH 3. Adhesion of both vegetative cells and spores of two Alicyclobacillus sp. to all materials studied was the most pronounced under acidic conditions, and adhesion was influenced mostly by electrostatic attractions. The most intensive adhesion of vegetative cells and spores at pH 3 was observed for DEAE followed by hydrophobic octyl and hydrophilic carboxyl surfaces. Overall, the lowest rate of adhesion between cells and model materials was observed at an alkaline pH. Consequently, prevention of adhesion should be based on the use of alkaline sanitizers and/or alkaline rinse water.

• Klíčová slova
• Alicyclobacillus sp., Cell adhesion, Model materials, Surface interaction, XDLVO model,
• MeSH
• Alicyclobacillus chemie   fyziologie   MeSH
• bakteriální adheze * MeSH
• koncentrace vodíkových iontů MeSH
• povrchové vlastnosti MeSH
• spory bakteriální chemie   fyziologie   MeSH
• Publikační typ
• časopisecké články MeSH

A biosynthetic pathway using pivalic acid as a starter unit was found in three bacterial species, Alicyclobacillus acidoterrestris, Rhodococcus erythropolis and Streptomyces avermitilis. When deuterium-labelled pivalic acid was added to A. acidoterrestris and R. erythropolis nutrient media it was incorporated into fatty acids to give rise to tert-butyl fatty acids (t-FAs). In addition, in R. erythropolis, pivalic acid was transformed into two starter units, i.e. isobutyric and 2-methylbutyric acid, which served as precursors of corresponding iso-even FAs and anteiso-FAs. In S. avermitilis the biosynthesis also yielded all three branched FAs; apart from this pathway, both pivalic and 2-methylbutyric acids were incorporated into the antibiotic avermectin.

• MeSH
• Alicyclobacillus metabolismus   MeSH
• antibakteriální látky biosyntéza   MeSH
• butyráty metabolismus   MeSH
• ivermektin analogy a deriváty   metabolismus   MeSH
• kyseliny pentanové metabolismus   MeSH
• mastné kyseliny biosyntéza   MeSH
• Rhodococcus metabolismus   MeSH
• Streptomyces metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 2-methylbutanoic acid MeSH Prohlížeč
• antibakteriální látky MeSH
• avermectin MeSH Prohlížeč
• butyráty MeSH
• ivermektin MeSH
• kyseliny pentanové MeSH
• mastné kyseliny MeSH
• pivalic acid MeSH Prohlížeč

Identification of molecular species of various N-acylated bacteriohopanehexol-mannosamides from the thermophilic bacterium Alicyclobacillus acidoterrestris by semipreparative HPLC and by RP-HPLC with ESI is described. We used triple-quadrupole type mass spectrometer, (1)H and (13)C NMR for analyzing this complex lipid. CD spectra of two compounds (model compound--7-deoxy-D: -glycero-D: -allo-heptitol obtained by stereospecific synthesis, and an isolated derivative of hopane) were also measured and the absolute configuration of both compounds was determined. On the basis of all the above methods, we identified the full structure of a new class of bacteriohopanes, represented by various N-acylated bacteriohopanehexol-mannosamides.

• MeSH
• acylace MeSH
• Alicyclobacillus chemie   růst a vývoj   MeSH
• amidy analýza   chemie   izolace a purifikace   MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací MeSH
• magnetická rezonanční spektroskopie MeSH
• mannosa analýza   chemie   MeSH
• plynová chromatografie s hmotnostně spektrometrickou detekcí MeSH
• tandemová hmotnostní spektrometrie MeSH
• teplota MeSH
• triterpeny analýza   chemie   izolace a purifikace   MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• amidy MeSH
• bacteriohopanehexol MeSH Prohlížeč
• mannosa MeSH
• triterpeny MeSH