Numerous commensal and pathogenic Gram-negative and Gram-positive bacteria are referred to as neutralophiles because they grow best at pH levels close to neutrality. Thus, exposure to harsh-to-mild acidic environments, such as those encountered in the digestive tract of animal hosts, in the phagosome of macrophages, in fermented foods, but also in the soil or in acid mine drainage, is a rather common encounter for neutralophiles during their life cycle. As a result, it is not surprising that most of them have evolved sophisticated molecular mechanisms to cope with low pH. These protective mechanisms provide neutralophiles with the ability to sense acid pH and keep under control the intracellular acidification of the cytoplasm, thus avoiding protons from reaching such harmful levels as to compromise cellular vitality, which relies on the proper functioning of many biological macromolecules at pH levels near neutrality. The aim of this chapter is to provide an overview of the most commonly employed, and best characterized, molecular systems in a number of Gram-positive and Gram-negative bacteria. How they work inside the cell and how their activity can be linked to virulence are highlighted. The biochemistry and distribution of the glutamate-dependent acid resistance system among orally acquired bacteria are described in some detail.

Acid survival mechanisms in neutralophilic bacteria / Pennacchietti, Eugenia; Giovannercole, Fabio; DE BIASE, Daniela. - STAMPA. - (2016), pp. 911-926. [10.1002/9781119004813.ch89].

Acid survival mechanisms in neutralophilic bacteria

PENNACCHIETTI, Eugenia;GIOVANNERCOLE, FABIO;DE BIASE, Daniela
2016

Abstract

Numerous commensal and pathogenic Gram-negative and Gram-positive bacteria are referred to as neutralophiles because they grow best at pH levels close to neutrality. Thus, exposure to harsh-to-mild acidic environments, such as those encountered in the digestive tract of animal hosts, in the phagosome of macrophages, in fermented foods, but also in the soil or in acid mine drainage, is a rather common encounter for neutralophiles during their life cycle. As a result, it is not surprising that most of them have evolved sophisticated molecular mechanisms to cope with low pH. These protective mechanisms provide neutralophiles with the ability to sense acid pH and keep under control the intracellular acidification of the cytoplasm, thus avoiding protons from reaching such harmful levels as to compromise cellular vitality, which relies on the proper functioning of many biological macromolecules at pH levels near neutrality. The aim of this chapter is to provide an overview of the most commonly employed, and best characterized, molecular systems in a number of Gram-positive and Gram-negative bacteria. How they work inside the cell and how their activity can be linked to virulence are highlighted. The biochemistry and distribution of the glutamate-dependent acid resistance system among orally acquired bacteria are described in some detail.
2016
Stress and environmental regulation of gene expression and adaptation in bacteria
9781119004813
9781119004882
acid stress; Escherichia coli; neutralophiles
02 Pubblicazione su volume::02a Capitolo o Articolo
Acid survival mechanisms in neutralophilic bacteria / Pennacchietti, Eugenia; Giovannercole, Fabio; DE BIASE, Daniela. - STAMPA. - (2016), pp. 911-926. [10.1002/9781119004813.ch89].
File allegati a questo prodotto
File Dimensione Formato  
Pennacchietti_Acid-survival-mechanisms_2016.pdf

solo utenti autorizzati

Tipologia: Versione editoriale (versione pubblicata con il layout dell'editore)
Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 1.84 MB
Formato Adobe PDF
1.84 MB Adobe PDF   Contatta l'autore

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/954769
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 2
  • ???jsp.display-item.citation.isi??? ND
social impact