TY - JOUR
T1 - Cyclic-di-adenosine monophosphate (c-di-AMP) is required for osmotic regulation in Staphylococcus aureus but dispensable for viability in anaerobic conditions
AU - Zeden, Merve S.
AU - Schuster, Christopher F.
AU - Bowman, Lisa
AU - Zhong, Qiyun
AU - Williams, Huw D.
AU - Gründling, Angelika
N1 - This research was supported by the European Research Council grant 260371 and the Wellcome Trust grant 100289 to A.G.; M.S.Z. is supported by a Medical Research Council Centre for Molecular Bacteriology and Infection (MRC CMBI) studentship and C.F.S. by the German research foundation (DFG) grant SCHU 3159/1-1.
PY - 2018/3/2
Y1 - 2018/3/2
N2 - Cyclic di-adenosine monophosphate (c-di-AMP) is a recently discovered signaling molecule important for the survival of Firmicutes, a large bacterial group that includes notable pathogens such as Staphylococcus aureus. However, the exact role of this molecule has not been identified. dacA, the S. aureus gene encoding the diadenylate cyclase enzyme required for c-di-AMP production, cannot be deleted when bacterial cells are grown in rich medium, indicating that c-di-AMP is required for growth in this condition. Here, we report that an S. aureus dacA mutant can be generated in chemically defined medium. Consistent with previous findings, this mutant had a severe growth defect when cultured in rich medium. Using this growth defect in rich medium, we selected for suppressor strains with improved growth to identify c-di-AMP-requiring pathways. Mutations bypassing the essentiality of dacA were identified in alsT and opuD, encoding a predicted amino acid and osmolyte transporter, the latter of which we show here to be the main glycine betaine-uptake system in S. aureus. Inactivation of these transporters likely prevents the excessive osmolyte and amino acid accumulation in the cell, providing further evidence for a key role of c-di-AMP in osmotic regulation. Suppressor mutations were also obtained in hepS, hemB, ctaA and qoxB, coding for proteins required for respiration. Furthermore, we show that dacA is dispensable for growth in anaerobic conditions. Together, these finding reveal an essential role for the c-di-AMP signaling network in aerobic, but not anaerobic, respiration in S. aureus.
AB - Cyclic di-adenosine monophosphate (c-di-AMP) is a recently discovered signaling molecule important for the survival of Firmicutes, a large bacterial group that includes notable pathogens such as Staphylococcus aureus. However, the exact role of this molecule has not been identified. dacA, the S. aureus gene encoding the diadenylate cyclase enzyme required for c-di-AMP production, cannot be deleted when bacterial cells are grown in rich medium, indicating that c-di-AMP is required for growth in this condition. Here, we report that an S. aureus dacA mutant can be generated in chemically defined medium. Consistent with previous findings, this mutant had a severe growth defect when cultured in rich medium. Using this growth defect in rich medium, we selected for suppressor strains with improved growth to identify c-di-AMP-requiring pathways. Mutations bypassing the essentiality of dacA were identified in alsT and opuD, encoding a predicted amino acid and osmolyte transporter, the latter of which we show here to be the main glycine betaine-uptake system in S. aureus. Inactivation of these transporters likely prevents the excessive osmolyte and amino acid accumulation in the cell, providing further evidence for a key role of c-di-AMP in osmotic regulation. Suppressor mutations were also obtained in hepS, hemB, ctaA and qoxB, coding for proteins required for respiration. Furthermore, we show that dacA is dispensable for growth in anaerobic conditions. Together, these finding reveal an essential role for the c-di-AMP signaling network in aerobic, but not anaerobic, respiration in S. aureus.
KW - Journal article
KW - Cyclic diadenosine monophosphate (c-di-AMP)
KW - Osmotic swelling
KW - Respiration
KW - Signaling
KW - Staphylococcus aureus (S. aureus)
U2 - 10.1074/jbc.M117.818716
DO - 10.1074/jbc.M117.818716
M3 - Article
C2 - 29326168
SN - 0021-9258
VL - 293
SP - 3180
EP - 3200
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 9
ER -