Fig 7.

S. pneumoniae (Sp) MnmM is involved in mnm⁵s²U tRNA modification. tRNA isolated from Sp cultures using MW methods were digested and analyzed through LC-MS Method 1. Modified nucleosides were purified tRNA from Sp strains: (1) Sp IU19835: D39 Δcps WT (spd_0565⁺, spd_0566⁺, spd_0567⁺) (black), (2) Sp IU19964: Δspd_0565-0566 markerless (ΔytqA) (dark gray), (3) Sp IU19966: Δspd_0567 markerless (ΔmnmM) (light gray), (4) Sp IU19968: Δspd_0565-0567 markerless (ΔytqAmnmM)(white), (5) Sp IU19974: Δspd_0567 markerless (ΔmnmM) ΔbgaA-Pzn-mnmM grown in Zn, (complementation of ΔmnmM) (gray stripped), and (6) Sp IU1824: original WT strain (IU1824) that has spd_0567 (Q152stop) mutation (black stripped). spd_0565 and spd_0566 encode the N-terminal and C-terminal of YtqA and spd_0567 encodes MnmM. Relative levels of each modification were determined by normalizing the mass abundance associated with each modification to the mass abundance of dihydrouridine in the same sample. The reported averages were calculated based on data acquired from three independent growth experiments. The star mark denotes the absence of modification or levels below the detection limit.