The secY-rpmJ region of the spc ribosomal protein operon in Escherichia coli: structural alterations affecting secY expression.
A unique feature of the spc ribosomal protein operon is that its region distal to the promoter contains a gene (secY) for an integral membrane protein, followed by an open reading frame termed X which has recently been proposed to encode a new ribosomal protein (protein B). We now show that the open reading frame X indeed directs the synthesis of a protein with electrophoretic mobilities similar to the B protein, and this supports the proposal that X may be more appropriately called rpmJ. Insertion of a plasmid sequence into the secY-rpmJ boundary of the chromosome caused a reduced expression of secY probably by destabilizing the secY part of the message. The results of complementation experiments suggested that a normal level of expression of rpmJ is not required for growth or protein secretion.
Ueguchi
C
C
Institute for Virus Research, Kyoto University, Japan.
Wittekind
M
M
Nomura
M
M
Akiyama
Y
Y
Ito
K
K
D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics*; D001692:Biological Transport; D002874:Chromosome Mapping; D004247:DNA / Q000235:genetics; D015180:Electrophoresis, Gel, Two-Dimensional; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development; D005784:Gene Amplification; D005786:Gene Expression Regulation; D005816:Genetic Complementation Test; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics; D009154:Mutation; D009876:Operon; D010957:Plasmids; D011401:Promoter Regions, Genetic; D012269:Ribosomal Proteins / Q000235:genetics* / Q000378:metabolism
D001426:Bacterial Proteins; D008565:Membrane Proteins; D012269:Ribosomal Proteins; D004247:DNA