The cytochromecd1nitrite reductase fromParacoccus pantotrophuscatalyses
the one electron reduction of nitrite to nitric oxide using two heme cofactors.
The site of nitrite reduction is thed1
heme, which is synthesized under anaer-obic conditions by usingnirECFD-LGHJNgene products.
One of the rate-limiting steps in protein folding has been shown to be the
cis–transisomerization of proline residues, catalysed by a range of peptidyl
prolylcis–transisomerases (PPIases). In the periplasmic space of Escherichia
coliand other Gram-negative bacteria, two PPIases, SurA and PpiD, have
been identified, which show high sequence similarity to the catalytic domain
of the small PPIase parvulin.
KdpD is a sensor kinase protein in the inner membrane of
Escherichia colicontaining four transmembrane regions.
The periplasmic loops connecting the transmembrane
regions are intriguingly short and proteasemapping allowed
us to only follow the translocation of the second periplasmic
loop. The results show that neither the Sec translocase nor
theYidCprotein are required formembrane insertion of the
second loop ofKdpD.
Proteins adsorbed on nanoparticles (NPs) are being used as biosensors and
in drug delivery. However, our understanding of the effect of NPs on the
structure of proteins is still in a nascent state. In this work we report
the unfolding behavior of the periplasmic domain of the ToxR protein
(ToxRp) of Vibrio choleraeon zinc oxide (ZnO) nanoparticles with a diam-eter of 2.5 nm.
Periplasmic binding proteins are abundant in bacteria by virtue of their
essential roles as high-affinity receptors in ABC transport systems and
chemotaxis. One of the best studied of these receptors is the so-called
glucose⁄galactose-binding protein. Here, we report the X-ray structure of
the Salmonella typhimuriumprotein bound to the physiologically relevant
ligand, (2R)-glyceryl-b-d-galactopyranoside, solved by molecular replace-ment, and refined to 1.87 A˚ resolution with RandR-free values of 17%
Targeting of proteins to and translocation across the
membranes is a fundamental biological process in all
organisms. In bacteria, the twin arginine translocation
(Tat) system can transport folded proteins. Here, we
demonstrate in vivo that the high potential iron-sulfur
protein (HiPIP) from Allochromatium vinosumis trans-located into the periplasmic space by the Tat system of
Escherichia coli. In vitro, reconstituted HiPIP precursor
(preHoloHiPIP) was targeted to inverted membrane
vesicles from E. ...
Inclusion bodies are insoluble protein aggregates usually found in recombi-nant bacteria when they are forced to produce heterologous protein species.
These particles are formed by polypeptides that cross-interact through
sterospecific contacts and that are steadily deposited in either the cell’s
cytoplasm or the periplasm.
In Gram-negative bacteria, the two-partner secretion pathway mediates the
secretion of TpsA proteins with various functions. TpsB transporters specifi-cally recognize their TpsA partners in the periplasm and mediate their trans-port through a hydrophilic channel.