Chemistry Reference
In-Depth Information
FIGURE 7.3
Other marine siderophores, including alterobactins, pseudoalterobactins, aerobactin, petrobactins, and vibriobactins.
(Adapted
from
Vraspir & Butler, 2009
.
NIH Public Access.)
(a)
(b)
FIGURE 7.4
Proposed models depicting electron transfer pathways for Shewanella oneidensis MR-1 (a) and Geobacter sulfurreducens (b)
during dissimilatory reduction of solid metal (hydr)oxides.
METAL ASSIMILATION IN BACTERIA
Bacteria are surrounded by rigid cell walls which give them their characteristic shapes, and enable them to live in
hypotonic environments without swelling and lysing their plasma membranes. The so-called Gram-negative
bacteria,
4
which we will mostly deal with here, have a thin cell wall surrounding their plasma membrane, covered
by an additional outer membrane. This defines four compartments
the outer membrane, the periplasm, the
plasma membrane, and the cytosol. This means that, for charged or even hydrated metal ions to enter the
e
4. This classification is based on whether or not the bacteria take up the Gram stain, devised by Christian Gram in 1884.
