The Library
Towards and understanding of multiple paralogues for metal-handling genes in a coastal cyanobacterium
Tools
Chu, Jie (2012) Towards and understanding of multiple paralogues for metal-handling genes in a coastal cyanobacterium. PhD thesis, University of Warwick.
|
Text
WRAP_THESIS_Chu_2012.pdf - Submitted Version Download (9Mb) | Preview |
Official URL: http://webcat.warwick.ac.uk/record=b2678559~S1
Abstract
Marine picocyanobacteria are the most abundant photosynthetic bacterioplankton
occupying a wide range of habitats across the world’s oceans. In order to survive
in such diverse habitats, these organisms have developed various mechanisms to
respond to specific environmental challenges they might encounter. One such
challenge for cyanobacteria is the acquisition and homeostasis of micronutrients
such as Zn and Cu, especially for those organisms occupying a variable
ecosystem with an erratic nutrient supply. Metallothioneins are metal-binding
proteins that potentially participate in such metal homeostasis mechanisms in
these marine picocyanobacteria.
Metallothioneins are small, cysteine-rich proteins capable of binding multiple
metal ions, and have attracted intense scientific interest since their discovery in
the 1950s. Over the last decade, they have been reported in every kingdom, from
prokaryotic to eukaryotic, from bacteria to plants, from worms to mammals.
Eukaryotic metallothioneins have been extensively studied. However,
characterisation of bacterial metallothioneins is still rare.
This research focused on the coastal cyanobacterium Synechococcus sp. CC9311,
which is unusual in possessing four metallothionein genes (sync_0853,
sync_1081, sync_2379 and sync_2426) while most marine picocyanobacteria
contain only one, or none. Three metallothioneins were comprehensively
characterised using a range of analytical and biophysical techniques. Mass
spectrometry and nuclear magnetic resonance studies combined with homology
modelling led to an unambiguous Zn3Cys8His cluster for BmtA0853, a highly
likely Zn4Cys9His2 cluster for BmtA2426, and three possible configurations for
BmtA1081. Analysis of gene expression profiles revealed that the four
metallothioneins selectively participated in zinc scavenging, zinc homeostasis,
cadmium detoxification, or protection from oxidising conditions. Growth of
Synechococcus sp. CC9311 under various metal treatments also revealed that this
coastal strain has developed a metal intensive physiology compared to the open
ocean strain Synechococcus sp. WH8102.
Item Type: | Thesis (PhD) | ||||
---|---|---|---|---|---|
Subjects: | Q Science > QP Physiology Q Science > QR Microbiology |
||||
Library of Congress Subject Headings (LCSH): | Cyanobacteria -- Genetics, Metallothionein, Marine bacteria | ||||
Official Date: | August 2012 | ||||
Dates: |
|
||||
Institution: | University of Warwick | ||||
Theses Department: | Molecular Organisation and Assembly in Cells | ||||
Thesis Type: | PhD | ||||
Publication Status: | Unpublished | ||||
Supervisor(s)/Advisor: | Blindauer, Claudia A.; Scanlan, David J. | ||||
Extent: | xix, 212 leaves : illustrations, charts. | ||||
Language: | eng |
Request changes or add full text files to a record
Repository staff actions (login required)
View Item |
Downloads
Downloads per month over past year