Distinct form I, II, III, and IV Rubisco proteins from the three kingdoms of life provide clues about Rubisco evolution and structure/function relationships.
There are four forms of ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) found in nature. Forms I, II, and III catalyse the carboxylation and oxygenation of ribulose 1,5-bisphosphate, while form IV, also called the Rubisco-like protein (RLP), does not catalyse either of these reactions. There appear to be six different clades of RLP. Although related to bona fide Rubisco proteins at the primary sequence and tertiary structure levels, RLP from two of these clades is known to perform other functions in the cell. Forms I, II, and III Rubisco, along with form IV (RLP), are thought to have evolved from a primordial archaeal Rubisco. Structure/function studies with both archaeal form III (methanogen) and form I (cyanobacterial) Rubisco have identified residues that appear to be specifically involved with interactions with molecular oxygen. A specific region of all form I, II, and III Rubisco was identified as being important for these interactions.
Tabita
F Robert
FR
Department of Microbiology, The Ohio State University, 484 West 12th Avenue, Columbus, Ohio 43210-1292, USA. Tabita.1@osu.edu
Satagopan
Sriram
S
Hanson
Thomas E
TE
Kreel
Nathan E
NE
Scott
Stephanie S
SS
D005075:Biological Evolution; D007527:Isoenzymes; D010944:Plants / Q000201:enzymology*; D012273:Ribulose-Bisphosphate Carboxylase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D013329:Structure-Activity Relationship
D007527:Isoenzymes; D012273:Ribulose-Bisphosphate Carboxylase