Editing Rossmann fold (section)

{{short description|Protein fold}}
{{missing information|more non-nucleotide functions|date=February 2021}}
{{Infobox protein family
| Symbol = NADP_Rossmann
| Name = NAD(P)-binding Rossmann fold
| image = 
| caption = 
| Pfam = 
| Pfam_clan = CL0063
| ECOD = 2003.1
| InterPro = 
| SMART = 
| PROSITE = 
| MEROPS =
| CATH =
| SCOP = 
| TCDB = 
| OPM protein = 
| CAZy = 
| CDD =
}}
{{Infobox protein family
| Name      = Rossmann-like alpha/beta/alpha sandwich fold
| Symbol    = Rossmann-like_a/b/a_fold
| image     = Alcohol dehydrogenase Rossmann.png
| caption   = NAD/NADP binding rossmann fold domains. The picture depicts the beta-alpha folding in alcohol dehydrogenase.
| InterPro  = IPR014729
| Pfam_clan = CL0039
}}
The '''Rossmann fold''' is a tertiary fold found in [[protein]]s that bind [[nucleotide]]s, such as enzyme [[cofactor (biochemistry)|cofactors]] [[flavin adenine dinucleotide|FAD]], [[Nicotinamide adenine dinucleotide|NAD<sup>+</sup>]], and [[NADP|NADP<sup>+</sup>]]. This fold is composed of alternating [[beta strand]]s and [[alpha helical]] segments where the beta strands are hydrogen bonded to each other forming an extended [[beta sheet]] and the alpha helices surround both faces of the sheet to produce a three-layered sandwich. The classical Rossmann fold contains six beta strands whereas Rossmann-like folds, sometimes referred to as '''Rossmannoid folds''', contain only five strands. The initial beta-alpha-beta (bab) fold is the most conserved segment of the Rossmann fold.<ref name="Hanukoglu_2015">{{cite journal | vauthors = Hanukoglu I | title = Proteopedia: Rossmann fold: A beta-alpha-beta fold at dinucleotide binding sites | journal = Biochemistry and Molecular Biology Education | volume = 43 | issue = 3 | pages = 206–9 | year = 2015 | pmid = 25704928 | doi = 10.1002/bmb.20849 | doi-access = free }}</ref> The motif is named after [[Michael Rossmann]] who first noticed this structural motif in the enzyme [[lactate dehydrogenase]] in 1970 and who later observed that this was a frequently occurring motif in nucleotide binding proteins.<ref name = "Lehninger_2013">{{cite book | vauthors = Cox MM, Nelson DL | title = Lehninger Principles of Biochemistry | date = 2013 | publisher = W.H. Freeman | location = New York | isbn = 978-1-4292-3414-6 | edition = 6th }}</ref>

Rossmann and Rossmannoid fold proteins are extremely common. They make up 20% of proteins with known structures in the [[Protein Data Bank]], and are found in more than 38% of [[KEGG]] metabolic pathways.<ref name=Medvedev_2019/> The fold is extremely versatile in that it can accommodate a wide range of ligands. They can function as metabolic enzymes, DNA/RNA binding, and regulatory proteins in addition to the traditional role.<ref name=Med/>