TY - JOUR
T1 - Mutational analysis of the role of HPr in Listeria monocytogenes
AU - Christensen, Douglas P.
AU - Benson, Andrew K.
AU - Hutkins, Robert W.
PY - 1999/5
Y1 - 1999/5
N2 - The regulatory role of HPr, a protein of the phosphotransferase system (PTS), was investigated in Listeria monocytogenes. By constructing mutations in the conserved histidine 15 and serine 46 residues of HPr, we were able to examine how HPr regulates PTS activity. The results indicated that histidine 15 was phosphorylated in a phosphoenolpyruvate (PEP) dependent manner and was essential for PTS activity. Serine 46 was phosphorylated in an ATP-dependent manner by a membrane-associated kinase. ATP-dependent phosphorylation of serine 46 was significantly enhanced in the presence of fructose 1,6- diphosphate and resulted in a reduction of PTS activity. The presence of a charge at position 15 did not inhibit ATP-dependent phosphorylation of serine 46, a finding unique to gram-positive PEP-dependent PTSs studied to this point. Finally, HPr phosphorylated at serine 46 does not appear to possess self-phosphatase activity, suggesting a specific phosphatase protein may be essential for the recycling of HPr to its active form.
AB - The regulatory role of HPr, a protein of the phosphotransferase system (PTS), was investigated in Listeria monocytogenes. By constructing mutations in the conserved histidine 15 and serine 46 residues of HPr, we were able to examine how HPr regulates PTS activity. The results indicated that histidine 15 was phosphorylated in a phosphoenolpyruvate (PEP) dependent manner and was essential for PTS activity. Serine 46 was phosphorylated in an ATP-dependent manner by a membrane-associated kinase. ATP-dependent phosphorylation of serine 46 was significantly enhanced in the presence of fructose 1,6- diphosphate and resulted in a reduction of PTS activity. The presence of a charge at position 15 did not inhibit ATP-dependent phosphorylation of serine 46, a finding unique to gram-positive PEP-dependent PTSs studied to this point. Finally, HPr phosphorylated at serine 46 does not appear to possess self-phosphatase activity, suggesting a specific phosphatase protein may be essential for the recycling of HPr to its active form.
UR - http://www.scopus.com/inward/record.url?scp=0032900603&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0032900603&partnerID=8YFLogxK
U2 - 10.1128/aem.65.5.2112-2115.1999
DO - 10.1128/aem.65.5.2112-2115.1999
M3 - Article
C2 - 10224008
AN - SCOPUS:0032900603
VL - 65
SP - 2112
EP - 2115
JO - Applied and Environmental Microbiology
JF - Applied and Environmental Microbiology
SN - 0099-2240
IS - 5
ER -