Pseudomonas aeruginosa T6SS-mediated molybdate transport contributes to bacterial competition during anaerobiosis

Abstract

Highlights d H2-T6SS mediates molybdate acquisition by secretion of ModA d Expression of H2-T6SS is activated by the master regulator Anr and anaerobiosis d ModA interacts with the outer membrane protein IcmP and uses it to deliver molybdate d The T6SS-ModA-IcmP system plays a role for P. aeruginosa

Differential Expression of Paraburkholderia phymatum Type VI Secretion Systems (T6SS) Suggests a Role of T6SS-b in Early Symbiotic Interaction

“…In P. aeruginosa T6SS has been shown to react to stress induced by subinhibitory concentrations of antibiotics such as kanamycin or polymyxins ( Jones et al, 2013 ; Vitale et al, 2020 ). Additionally, P. aeruginosa T6SS facilitates the uptake of molybdate and increases its competitiveness ( Wang et al, 2021 ). Our results showed that the expression of P. phymatum T6SS was not influenced by the presence of subinhibitory and inhibitory concentrations of several tested antibiotics, at least not at the transcriptional level (data not shown).…”

Roles of Type VI Secretion System in Transport of Metal Ions

“…Like the previously discovered two H1-T6SS effectors Tse1 and Tse3, which can hydrolyze peptidoglycan and provide a competitive fitness advantage (Russell et al, 2011), H2-T6SS improves bacterial competition by promoting molybdate (MoO 4 2− ) acquisition under anaerobic conditions (Wang et al, 2021). As a transcriptional regulator, Anr can activate H2-T6SS expression under anaerobic conditions (Wang et al, 2021). Anr in P. aeruginosa controls the switch from aerobic to anaerobic growth and plays a pivotal role in adapting to microaerobic or anoxic conditions (Ugidos et al, 2008;Tata et al, 2017).…”

“…In P. aeruginosa, the H2-T6SS secreted ModA has been identified as a molybdate-binding protein and mediated molybdate acquisition. Moreover, a ModA partner that participates in molybdate transport has also been identified as IcmP that is an insulin-cleaving metalloproteinase outer membrane protein (Wang et al, 2021). The T6SS-ModA-IcmP system contributes to bacterial virulence and participates in bacterial competition under anaerobic conditions.…”

“…Studies have shown that the molybdenum homeostasis of P. aeruginosa PA1006 is necessary for nitrate utilization, biofilm formation, and virulence (Filiatrault et al, 2013;Tombline et al, 2013). In a mouse model of acute pneumonia, the P. aeruginosa clpV2, modA, and anr mutants exhibited attenuated virulence, indicating that the H2-T6SS-mediated molybdate transport system contributes to the resistance to host nutritional immunity (Wang et al, 2021). Like the previously discovered two H1-T6SS effectors Tse1 and Tse3, which can hydrolyze peptidoglycan and provide a competitive fitness advantage (Russell et al, 2011), H2-T6SS improves bacterial competition by promoting molybdate (MoO 4 2− ) acquisition under anaerobic conditions (Wang et al, 2021).…”

“…In a mouse model of acute pneumonia, the P. aeruginosa clpV2, modA, and anr mutants exhibited attenuated virulence, indicating that the H2-T6SS-mediated molybdate transport system contributes to the resistance to host nutritional immunity (Wang et al, 2021). Like the previously discovered two H1-T6SS effectors Tse1 and Tse3, which can hydrolyze peptidoglycan and provide a competitive fitness advantage (Russell et al, 2011), H2-T6SS improves bacterial competition by promoting molybdate (MoO 4 2− ) acquisition under anaerobic conditions (Wang et al, 2021). As a transcriptional regulator, Anr can activate H2-T6SS expression under anaerobic conditions (Wang et al, 2021).…”