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MATHEMATICAL AND COMPUTATIONAL BIOLOGYAND NUMERICAL ANALYSIS
BIOMATHEMATICS AND NUMERICAL ANALYSIS BOOK SERIES
Direttore
Ezio VUniversità di Torino
Comitato scientifico
Leonard Peter BUniversità di Verona
Luigi BUniversità di Firenze
Alberto ’OInternational Prevention Research Institute
Stefano D MUniversità di Padova
Mario GUniversità di Torino
Horst MUniversität Osnabrück
Piero MUniversità di Pisa
Sergei PUniversity of Leicester
MATHEMATICAL AND COMPUTATIONAL BIOLOGYAND NUMERICAL ANALYSIS
BIOMATHEMATICS AND NUMERICAL ANALYSIS BOOK SERIES
Essentially, all models are wrong, but some are useful.
George E.P. B
The purpose of this book series is twofold.
On one hand, to bring together works discussing various aspects of math-ematical models with life science applications, encompassing all fieldswithin this realm: population theory, cell dynamics, epidemiology, ecology,metapopulations, regional dynamics and geographical invasions, individualand collective animal movement, eco–epidemiology, spread of epidemics,pattern formation, evolutionary dynamics. Also other topics not included inthe above list could be considered. We would like to emphasize interdisci-plinary approaches, comparing modeling techniques generally applied inecology and those used in other life sciences.
On the other hand, we welcome contributions in all fields of numericaltechniques, such as, for instance, numerical methods in approximationtheory, differential equations, linear algebra, computer aided geometricdesign, optimization.
Sonia Senesi
Bacillus Cereus Swarming Motility
An Elegant Behavior Enhancing Invasive Infectious DiseasesToxin Production and Environmental Colonization
Aracne editrice
Copyright © MMXXGioacchino Onorati editore S.r.l. – unipersonale
via Vittorio Veneto, Canterano (RM)
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No part of this book may be reproducedby print, photoprint, microfilm, microfiche, or any other means,
without publisher’s authorization.
Ist edition: January
Contents
Summary
Introduction
Chapter IThe Discovery of Swarming in Bacillus Cereus
Chapter IITraits of Swarming Behavior Peculiar to Bacillus Cereus
Chapter IIIGenetic Control of Swarming in Bacillus Cereus
Chapter IVSwarming by Bacillus Cereus Facilitates Invasive Infections
Chapter VEnhancement of Toxin Secretion by Swarmer Cells of Bacillus Cereus
Chapter VIEnvironmental Advantages
Concluding Remarks
Acknowledges
References
Summary
Most flagellated bacteria may experience two main types of flagellum–drivenmotility, swimming and swarming, depending on whether they are prop-agated in liquid or solid media. Swimming is brought about by individualcells, while swarming is a social behavior enabling flagellated bacteria toco–operatively move across moist surfaces. This specialized form of surfacetranslocation is coupled with a complex process leading vegetative swimmercells to differentiate into a swarmer–cell state. Swarmer cells are longer,harbor a higher number of flagella, do not divide, and posses the uniqueability to coordinately move across surfaces in multicellular rafts. Herein, isdescribed the ability of Bacillus cereus to undergo swarmer–cell differentia-tion allowing this microorganism to move by swarming atop solid surfaces.Swarming by Bacillus cereus takes place under a wide range of growth condi-tions: this versatility is ecologically relevant, since it allows this bacterium toadapt swarming motility to various environmental changes. Swarming byBacillus cereus is also medically important: swarmer cells are more virulent,prone to invade host tissues and to produce higher amounts of toxins. Char-acterization of swarming deficient mutants highlights that flagellar genes aswell as genes governing different cellular functions and metabolic pathwaysare involved in swarmer–cell differentiation. The environmental and geneticrequirements for swarming and the role played by B. cereus in the virulencethis opportunistic pathogen may exert are outlined.
