Prokaryotic translation initiation factor IF3 is an elongated protein consisting of two crystallizable domains.
We show that translation initiation factor IF3 can be split into two fragments of nearly equal size by the Escherichia coli outer membrane protease omptin. Circular dichroism and small-angle neutron scattering show that the two fragments are structured as domains. Each domain is relatively compact, and they are separated by about 45 A in intact IF3. Thus IF3 is an elongated protein that consists of two well-separated domains. We suggest that these two domains are involved in ribosome binding across the cleft of the 30S ribosome. We also report the crystallization of each domain of IF3.
Kycia
J H
JH
Biology Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
Biou
V
V
Shu
F
F
Gerchman
S E
SE
Graziano
V
V
Ramakrishnan
V
V
D002942:Circular Dichroism; D003460:Crystallization; D004926:Escherichia coli / Q000737:chemistry*; D010448:Peptide Initiation Factors / Q000737:chemistry*; D039665:Prokaryotic Initiation Factor-3; D017433:Protein Structure, Secondary; D012269:Ribosomal Proteins / Q000737:chemistry
D010448:Peptide Initiation Factors; D039665:Prokaryotic Initiation Factor-3; D012269:Ribosomal Proteins