title: The role of surface charge and hydrophobicity in the attachment of Anoxybacillus flavithermus isolated from milk powder.
abstract: The aim of the present study was to investigate the attachment mechanisms that enable the thermophile Anoxybacillus flavithermus (B12) to attach to stainless-steel surfaces. Passing a B12 culture through a column of stainless-steel chips, collecting the first cells to pass through, re-culturing, and repeating the process six times, resulted in the isolation of a mutant, labeled X7, with tenfold reduced ability to attach to stainless steel as well as a reduced ability to attach to plastic. A comparison of bacterial cell-surface properties indicated that X7 was less hydrophobic than its parental strain B12. Cell-surface charge measurements also suggest that X7 had a lower net-negative surface charge. Disruption of extracellular polysaccharides and DNA appeared to have no effect on the attachment process. Removal of surface proteins caused a reduction in attachment of both B12 and X7, suggesting surface protein involvement in attachment.
authors.affiliation: Institute of Food, Nutrition and Human Health, Massey University, Palmerston North, New Zealand. J.S.Palmer@massey.ac.nz
authors.forename: J S
authors.initials: JS
authors.lastname: Palmer
authors.forename: S H
authors.initials: SH
authors.lastname: Flint
authors.forename: J
authors.initials: J
authors.lastname: Schmid
authors.forename: J D
authors.initials: JD
authors.lastname: Brooks
mesh_terms: D058677:Anoxybacillus / Q000302:isolation & purification* / Q000502:physiology*; D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000032:analysis; D018441:Biofilms; D015169:Colony Count, Microbial; D003611:Dairy Products / Q000382:microbiology*; D057927:Hydrophobic and Hydrophilic Interactions; D008565:Membrane Proteins / Q000302:isolation & purification / Q000378:metabolism; D010969:Plastics; D019105:Random Amplified Polymorphic DNA Technique; D013193:Stainless Steel; D013499:Surface Properties
chemical_list: D001426:Bacterial Proteins; D008565:Membrane Proteins; D010969:Plastics; D013193:Stainless Steel