Advanced

Redox Regulation and Stress Responses - Studies in Bacillus subtilis

Larsson, Jonas LU (2005)
Abstract (Swedish)
Popular Abstract in Swedish

Redoxreaktioner är centrala i många livsnödvändiga funktioner såsom anabol och katabol metabolism. Det är därför viktigt att känna av och reglera cellens redoxstatus. En viktig komponent som påverkar detta är tillgången på syre. När syretillgången förändras så förändras den intracellulära redoxstatusen, vilket genererar en stress för cellen. Denna stress leder till ett förändrat uttryck av gener, kodande för proteiner som kan hjälpa till att återställa redoxbalansen. Denna avhandling presenterar olika aspekter av vad som ytterst orsakar denna stress och hur cellerna hanterar den.



Redoxsensorn Rex (YdiH) från Bacillus subtilis har karakteriserats. Rex hjälper cellen att... (More)
Popular Abstract in Swedish

Redoxreaktioner är centrala i många livsnödvändiga funktioner såsom anabol och katabol metabolism. Det är därför viktigt att känna av och reglera cellens redoxstatus. En viktig komponent som påverkar detta är tillgången på syre. När syretillgången förändras så förändras den intracellulära redoxstatusen, vilket genererar en stress för cellen. Denna stress leder till ett förändrat uttryck av gener, kodande för proteiner som kan hjälpa till att återställa redoxbalansen. Denna avhandling presenterar olika aspekter av vad som ytterst orsakar denna stress och hur cellerna hanterar den.



Redoxsensorn Rex (YdiH) från Bacillus subtilis har karakteriserats. Rex hjälper cellen att konservera energi när syre inte är tillgängligt, vilket sker genom att koordinera tre system som är viktiga för tillväxt vid låga syrehalter.



När bakterier exponeras för skadliga kväveföreningar induceras en stress på bakteriecellen. Avhandlingen visar att cellens svar inkluderar två system. Ett är induceringsbart (hmp) och använder sig av ett hemoglobin-liknande protein för att oskadliggöra kväveföreningarna. Det andra systemet (yjbIH) ger ett konstitutivt skydd mot denna typ av stress.



Avhandlingen presenterar även ett hittills okarakteriserat protein (YjbH) som har en nyckelroll i kontroll av den globala regulatorn Spx, vilken i sin tur är involverad i hanteringen av svavelbryggor. (Less)
Abstract
Redox reactions are central to all organisms to sustain life. Both anabolic and catabolic metabolism depends on them. It is thus vital to sense and adjust the redox balance in the cell. One major factor affecting the redox status is the level of oxygen present. Transitions between different oxygen concentrations change the redox status and among other things, confer a stress upon the cells. This stress ultimately leads to altered expression levels of genes necessary to cope with the new conditions. In this thesis different aspects of what ultimately causes stressful situations, and what bacteria can do to counteract them are analysed.



The redox-sensing protein Rex (YdiH) from Bacillus subtilis is characterised. Rex... (More)
Redox reactions are central to all organisms to sustain life. Both anabolic and catabolic metabolism depends on them. It is thus vital to sense and adjust the redox balance in the cell. One major factor affecting the redox status is the level of oxygen present. Transitions between different oxygen concentrations change the redox status and among other things, confer a stress upon the cells. This stress ultimately leads to altered expression levels of genes necessary to cope with the new conditions. In this thesis different aspects of what ultimately causes stressful situations, and what bacteria can do to counteract them are analysed.



The redox-sensing protein Rex (YdiH) from Bacillus subtilis is characterised. Rex adjusts the cell in a way that enables conservation of energy by means other than aerobic respiration. This is accomplished by coordinating the regulation of three systems involved in growth at low oxygen levels.



Exposure of cells to damaging nitrogen compounds exerts a stress upon the bacteria. This work shows that the cellular response involves two systems. One is an inducible system (hmp) involving a haemoglobin-like protein for direct detoxification of the nitrogen compounds, while the other system confers a constitutive protection (yjbIH).



The thesis also describes a hitherto uncharacterised protein (YjbH), which has a key role in the control of the global regulator Spx, which in turn is involved in disulphide stress management. (Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • Prof. Dr. Völker, Uwe, Laboratory for Functional Genomics, Medical School Ernst-Moritz-Arndt-University, D-17489 Greifswald
organization
publishing date
type
Thesis
publication status
published
subject
keywords
redox sensor, oxygen sensor, reactive nitrogen species, RNS, Biology, Biologi, Microbiology, bacteriology, virology, mycology, bakteriologi, Mikrobiologi, virologi, mykologi, Bacillus subtilis, Rex, yjbI, ydiH, yjbH, redox regulation
pages
94 pages
publisher
Cell and Organism Biology Lund University Sölvegatan 35 SE-22362 Lund
defense location
Biology lecture hall, Sölvegatan 35, Lund
defense date
2005-10-14 09:00
ISBN
91-85067-24-5
language
English
LU publication?
yes
id
006a93e0-1b2b-49ca-861a-e6065b0d905d (old id 545441)
date added to LUP
2007-09-05 10:13:23
date last changed
2016-09-19 08:45:10
@phdthesis{006a93e0-1b2b-49ca-861a-e6065b0d905d,
  abstract     = {Redox reactions are central to all organisms to sustain life. Both anabolic and catabolic metabolism depends on them. It is thus vital to sense and adjust the redox balance in the cell. One major factor affecting the redox status is the level of oxygen present. Transitions between different oxygen concentrations change the redox status and among other things, confer a stress upon the cells. This stress ultimately leads to altered expression levels of genes necessary to cope with the new conditions. In this thesis different aspects of what ultimately causes stressful situations, and what bacteria can do to counteract them are analysed.<br/><br>
<br/><br>
The redox-sensing protein Rex (YdiH) from Bacillus subtilis is characterised. Rex adjusts the cell in a way that enables conservation of energy by means other than aerobic respiration. This is accomplished by coordinating the regulation of three systems involved in growth at low oxygen levels.<br/><br>
<br/><br>
Exposure of cells to damaging nitrogen compounds exerts a stress upon the bacteria. This work shows that the cellular response involves two systems. One is an inducible system (hmp) involving a haemoglobin-like protein for direct detoxification of the nitrogen compounds, while the other system confers a constitutive protection (yjbIH).<br/><br>
<br/><br>
The thesis also describes a hitherto uncharacterised protein (YjbH), which has a key role in the control of the global regulator Spx, which in turn is involved in disulphide stress management.},
  author       = {Larsson, Jonas},
  isbn         = {91-85067-24-5},
  keyword      = {redox sensor,oxygen sensor,reactive nitrogen species,RNS,Biology,Biologi,Microbiology,bacteriology,virology,mycology,bakteriologi,Mikrobiologi,virologi,mykologi,Bacillus subtilis,Rex,yjbI,ydiH,yjbH,redox regulation},
  language     = {eng},
  pages        = {94},
  publisher    = {Cell and Organism Biology Lund University Sölvegatan 35 SE-22362 Lund},
  school       = {Lund University},
  title        = {Redox Regulation and Stress Responses - Studies in Bacillus subtilis},
  year         = {2005},
}