Talk:Disulfide bond

Cytoplasmic disulfide bonds in eukaryotes
The Hatahet et al. paper says that disulfide bonds are not stable in the cytoplasm of E. coli because it is a reducing environment. However, neither that paper nor Sevier et al. say the same about eukaryotes. Certainly the proteins are stable in the endoplasmic reticulum where they are created. There are probably other organelles where they are stable as well. If "usually proteins secreted to the extracellular medium" is true for eukaryotes, an additional source is needed to support this. 140.233.203.193 (talk) 18:17, 2 March 2012 (UTC)

Cys-cys bonds
Quoting from the text:
 * When two cysteine amino acids bond to each other, they do so through a disulfide bond.

Ouch. No cys-cys dipeptides? David M

Disulphide bonds in bacteria
I think that the section on disuplhide bonds in bacteria should be made clearer. I am a microbiologist and I'm really unsure to what you are refering when you say as a reversible switch that turns a protein on or off when bacterial cells are exposed to oxidation reactions.

Also bacteria do have the ability to form disulphide bonds but only in the periplasm where it is an oxidizing enviroment.

Nick

Formation rates
Is there any info on rates of formation? Or even some references. This is a complicated question, however it may be good to address it rather than ignore it. For instance: rate of thiol to thiol disulfide formation vs rate of CYS to CYS disulfide formation, etc.

Spamming Wikipedia
Biologicalworld.com has spammed wikipedia like no tomorrow. He is a site of only a few pages and a LOT of adsense. Not much information is given except for "protocols" which are not referenced, and cannot be trusted from a site of that quality.

check: Links from Wikipedia

The following have been cleaned up:

and many more Sciencetalks (talk) —Preceding comment was added at 03:03, 4 January 2008 (UTC)
 * en.wikipedia.org/wiki/Plasmid
 * en.wikipedia.org/wiki/Gel_electrophoresis
 * en.wikipedia.org/wiki/Green_fluorescent_protein
 * en.wikipedia.org/wiki/Homology_(biology)
 * en.wikipedia.org/wiki/HeLa
 * en.wikipedia.org/wiki/Protease
 * en.wikipedia.org/wiki/Restriction_enzyme
 * en.wikipedia.org/wiki/Petri_dish
 * en.wikipedia.org/wiki/Structural_domain
 * en.wikipedia.org/wiki/Trypsin
 * en.wikipedia.org/wiki/Oligonucleotide
 * en.wikipedia.org/wiki/Transmission_electron_microscope
 * en.wikipedia.org/wiki/Agar_plate
 * en.wikipedia.org/wiki/Calcium_phosphate
 * en.wikipedia.org/wiki/Disulfide_bond
 * en.wikipedia.org/wiki/Denaturation_(biochemistry)
 * en.wikipedia.org/wiki/DNA_ligase
 * en.wikipedia.org/wiki/Wild_type
 * en.wikipedia.org/wiki/Tissue_culture
 * en.wikipedia.org/wiki/Transmission_electron_microscopy
 * en.wikipedia.org/wiki/Reporter_gene
 * en.wikipedia.org/wiki/Northern_blot
 * en.wikipedia.org/wiki/Protein_engineering
 * en.wikipedia.org/wiki/Sticky_end/blunt_end
 * en.wikipedia.org/wiki/Taq_polymerase
 * en.wikipedia.org/wiki/Protein_domain
 * en.wikipedia.org/wiki/Coomassie
 * en.wikipedia.org/wiki/Native_state
 * en.wikipedia.org/wiki/Chinese_Hamster_Ovary_cell
 * en.wikipedia.org/wiki/Peptidase
 * en.wikipedia.org/wiki/Visking_tubing
 * en.wikipedia.org/wiki/Streptavidin
 * en.wikipedia.org/wiki/Microtiter_plate
 * en.wikipedia.org/wiki/Subcloning
 * en.wikipedia.org/wiki/Ion_exchange_chromatography
 * en.wikipedia.org/wiki/Thermal_cycler
 * en.wikipedia.org/wiki/Bovine_serum_albumin
 * en.wikipedia.org/wiki/Phosphate_buffered_saline
 * en.wikipedia.org/wiki/Glutathione_S-transferase
 * en.wikipedia.org/wiki/HEPES
 * en.wikipedia.org/wiki/Ortholog
 * en.wikipedia.org/wiki/Proteases
 * en.wikipedia.org/wiki/Salting_out
 * en.wikipedia.org/wiki/Fetal_bovine_serum
 * en.wikipedia.org/wiki/Proteolytic_enzyme
 * en.wikipedia.org/wiki/DNA_end
 * en.wikipedia.org/wiki/Supernatant
 * en.wikipedia.org/wiki/ABTS
 * en.wikipedia.org/wiki/Conserved_sequence
 * en.wikipedia.org/wiki/Peptide_mass_fingerprinting
 * en.wikipedia.org/wiki/Dithiothreitol
 * en.wikipedia.org/wiki/Uranyl_acetate

Corrections needed
There are quite a few mistakes in this article. I have fixed some, but many remain. For example, it can't be stated that in-vivo disulfide rearrangement reactions (or other reactions involving disulfides) are intra-molecular. Disulfide formation/destruction/isomerization is generally a catalyzed process in living cells, and catalysis usually involves formation of inter-molecular mixed disulfide bond with the catalyst. I hope to find some time to add a section on how disulfide bonds are formed and destroyed in different compartments of prokaryotic and eukaryotic cells. The importance of disulfide bonds in living organisms is understated. For example, the production of deoxyribonucleotides (building blocks of the genetic code) involves an enzyme called ribonucleotide reductase, with a disulfide bond at it's catalytic heart. The numbering of the figures should be removed, as now some figures are numbered while others are not. Thioredoxins usually do not have vicinal Cys. The catalytic motif in Trx is CXXC. It usually participates in the reduction of disulfide bonds in cytoplasm with an indirect role of oxidation of extracytoplasmic proteins through an electron relay such as DsbD in E. coli. Naming cytoplasm (redox potential ~-300 mV) as reducing environment and e.g. endoplasmic reticulum (-160 mV) as oxidizing is misleading, i.e. standard redox potential of oxygen (O2) is +620 mV. Fermmyt (talk) 23:35, 4 October 2013 (UTC)