文档介绍：Preface
The local environment of the anisms and cells in large industrial
bioreactors varies over a broader range than in small laboratory reactors, spin-
ner or shake flasks, because of the higher heterogeneity of the cultivation me-
dium caused by the longer global mixing time. In addition the turbulence inten-
sity and local shear forces are exacerbated with the increasing scale of the reac-
tors. The strong fluctuation of these local values causes stress to the micro-or-
ganisms and cells.
In the last 20 years, several research groups have dealt with the investigation
of the influence of stress on anisms, animal and plant cells. The last
review by . Merchuk, published in 1991, dealt with shear effects [1]. However,
recent molecular biological investigations indicate that the stress caused by fluid
dynamic stress (shear and turbulence), extreme values of process variables
(temperature,pH-value,concentrations of dissolved oxygen,glucose,phosphate,
various salts), metabolically harmful substances (latic acide, ammonia, ethanol
and various other solvents) plex metabolic processes cause similar re-
sponses in the cells. These molecular biological fundamentals are treated in the
first chapter entitled “Function and regulation of temperature inducible bac-
terial proteins on the cellular metabolism” by .
In this volume not all stress types are treated. Various aspects have been re-
viewed recently by various authors: .“The effects of oxygen on binant
protein expression” by Konz et al. [2]. The “Mechanisms by which bacterial cells
respond to pH” was considered in a Symposium in 1999 [3] and solvent effects
were reviewed by de Bont in the article “Solvent-tolerant bacteria in biocata-
lysis”[4]. Therefore, these aspects are not considered in this volume. Influence
of fluid dynamical stresses on anism,animal and plant cells are in cen-
ter of interest in this volume. In chapter 2, H.-J. Henzler discusses the quantita-
tive eval