... Similar to SopF, a T3SS1 effector of Salmonella enterica serovar typhimurium which binds to multiple PIs -PI(3)P, PI(3,5)P2 and PI(3,4,5)P3, (Lau et al., 2019) PlpD, a T5SS effector of Pseudomonas aeruginosa which binds to multiple PIs -PI, PI(4)P, PI(4,5)P2 and PI(3,4,5)P3 (da Mata Madeira et al., 2016) and FplA, another T5SS effector of Fusobacterium nucleatum which binds to multiple PIs -PI(3,5)P2, PI(4,5)P2 and PI(3,4,5)P3 (Casasanta et al., 2017) as revealed by protein lipid overlay assays, recombinant PemB also binds to multiple phosphoinositides PI, PI(5)P, PI(3,4,5)P3 and PI(3,5)P2 in vitro with stronger affinity as compared to the other phosphoinositides, delineated by our ITC experiments. On comparative analyses of binding affinities, revealed by different quantitative methods like isothermal titration calorimetry, surface plasmon resonance and biolayer interferometry, among other known effector-phosphoinositide complexes from previous literature reports, we find that SidM, SetA and LtpM, three T4SS effectors of Legionella pneumophila, bind to PI(4)P with K d of 56 nM (ITC), (Del Campo et al., 2014) PI(3)P with K d of 806 nM (SPR) (Jank et al., 2012) and PI(3)P with K d of 591 nM (SPR) (Levanova et al., 2019) respectively and OpiA, a T6SS ii effector of Francisella tularensis binds to PI(3)P with K d of 194 nM (BLI), (Ledvina et al., 2018) implying good agreement with our experimental results. ...