What is a Proton Sink and How Does NH4Cl Act as One?

[Grebo]

Ok, so i was talking to someone regarding the use of NH4Cl for the disruption of endosomal acidosis of proteins. ( Late endosomes decrease in pH to release receptors from their ligands during Endocytosis of cell signalling). I wagered that the NH4Cl was acting as some sort of channel blocker for the influx of Protons and they stated that they read it acts as a "Proton sink" buy crossing the endosomal membrane (very hydrophobic) and inhibiting the influx of protons.
i asked what the hell a proton sink is and they just replied that that wasnt important just accept that it is a proton sink and it is easier to understand.
Well, F' That SH#t man. I want to know what a proton sink is and how NH4Cl, a very polar salt is a: going to cross the endosomal membrane (without the aid of a proton channel) and b: going to elicite a "proton sink" whatever that is...
Anyone want to explain the proton sink idea to me cause I have no idea what that means.

 

[Navin A S]

A proton sink is a substance or molecule that can accept protons (H+) from its environment. In the case of NH4Cl, it can accept protons from the endosomal membrane, thus reducing the acidity of the endosome and allowing the receptors to be released from their ligands. The NH4Cl molecule is hydrophilic, so it can easily cross the endosomal membrane and effectively act as a "proton sink" by accepting protons and reducing the acidity of the endosome.

 

[ravenprp]

A proton sink is a term used to describe a substance or molecule that can absorb or neutralize excess protons in a solution. This is important in biological systems, as protons are involved in many cellular processes and their levels must be regulated. In the context of endosomal acidosis, NH4Cl acts as a proton sink by crossing the endosomal membrane and binding to excess protons, preventing them from entering the endosome and maintaining a more neutral pH level.

NH4Cl is a polar salt, but it can still cross the endosomal membrane due to its small size and the presence of channels and transporters that allow small molecules to pass through. Once inside the endosome, NH4Cl dissociates into ammonium (NH4+) and chloride (Cl-) ions. The ammonium ions are positively charged and can bind to excess protons, acting as a proton sink.

In summary, NH4Cl acts as a proton sink by crossing the endosomal membrane and binding to excess protons, preventing them from contributing to the acidification of the endosome. This helps to maintain a more neutral pH level and allows for the proper functioning of cellular processes.