TABLE 6.
Summary of fragment ions produced during MS/MS of the mutanolysin-released m/z 2432.99 parent ion
|
m/z
|
Δcalc-obsa
|
Ion
typeb
|
Proposed
structurec
|
|
|---|---|---|---|---|
| Observed | Calculated | |||
| 110.07 | 110.15 | 0.08 | Immonium | |
| 195.09 | 195.17 | 0.09 | i | HG |
| 247.13 | 247.22 | 0.09 | a2 | HH |
| 260.10 | 260.23 | 0.13 | i | GW |
| 275.13 | 275.24 | 0.12 | b2 | HH |
| 332.15 | 332.21 | 0.06 | i | HHG |
| 373.17 | 373.35 | 0.18 | i | l-Ala-d-iGln-m-Dap |
| 384.19 | 384.28 | 0.09 | i-H2O | d-iGln-(T-)m-Dap |
| 395.30 | 395.19 | −0.11 | i-28 | HHH |
| 397.16 | 397.28 | 0.12 | i | HGW |
| 412.18 | 412.32 | 0.14 | b3 | HHH |
| 483.26 | 483.34 | 0.08 | i-H2O | d-iGln-(VT-)m-Dap |
| 506.33 | 506.37 | 0.04 | i-H2O | ILPVT |
| 521.25 | 521.34 | 0.09 | a4 | HHHH |
| 549.24 | 549.36 | 0.12 | b4 | HHHH |
| 623.33 | 623.49 | 0.16 | i | HGWIL |
| 658.31 | 658.39 | 0.08 | a5 | HHHHH |
| 686.30 | 686.44 | 0.14 | b5 | HHHHH |
| 784.36 | 784.42 | 0.06 | i | HHHHGW |
| 795.37 | 795.48 | 0.11 | a6 | HHHHHH |
| 823.36 | 823.45 | 0.09 | b6 | HHHHHH |
| 880.38 | 880.49 | 0.11 | b7 | HHHHHHG |
| 897.41 | 897.59 | 0.18 | c7 | HHHHHHG |
| 1034.51 | 1034.64 | 0.13 | i | HHHHGWIL |
| 1054.46 | 1054.56 | 0.10 | a8 | HHHHHHGW |
| 1082.46 | 1082.61 | 0.15 | b8 | HHHHHHGW |
| 1167.55 | 1167.73 | 0.19 | a9 | HHHHHHGWI |
| 1171.57 | 1171.91 | 0.35 | i | HHHHHGWIL |
| 1195.54 | 1195.69 | 0.15 | b9 | HHHHHHGWI |
| 1280.63 | 1280.96 | 0.33 | a10 | HHHHHHGWIL |
| 1308.62 | 1308.83 | 0.21 | b10 | HHHHHHGWIL |
| 1477.73 | 1477.03 | −0.71 | i-NH3 | HHHGWILPVT-m-Dap-d-iGln |
| 1504.75 | 1504.92 | 0.18 | b12 | HHHHHHGWILPV |
| 1587.78 | 1587.03 | −0.75 | b13-H2O | HHHHHHGWILPVT |
| 1747.87 | 1748.23 | 0.36 | y12 | GlcNH2-(β1-4)-MurNAc-[l-Ala-d-iGln-(HGWILPVT-) m-Dap) |
| 1794.90 | 1795.24 | 0.33 | c14 | HHHHHHGWILPVT-m-Dap |
| 1860.92 | 1861.25 | 0.34 | a15-NH3 | d-iGln-(HHHHHHGWILPVT-)m-Dap |
| 1884.93 | 1885.38 | 0.45 | y13 | GlcNH2-(β1-4)-MurNAc-[l-Ala-d-iGln-(HHGWILPVT-) m-Dap) |
| 1922.96 | 1923.33 | 0.37 | c15 | d-iGln-(HHHHHHGWILPVT-)m-Dap |
| 2021.99 | 2022.43 | 0.43 | y14 | GlcNH2-(β1-4)-MurNAc-[l-Ala-d-iGln-(HHHGWILPV T-)m-Dap) |
| 2066.63 | 2067.41 | 0.78 | -d | lactoyl-[l-Ala-d-iGln-(HHHHHHGWILPVT-)m-Dap] |
| 2159.05 | 2159.41 | 0.36 | y15 | GlcNH2-(β1-4)-MurNAc-[l-Ala-d-iGln-(HHHHGWILPV T-)m-Dap) |
| 2271.78 | 2272.80 | 1.02 | -e | MurNAc-[l-Ala-d-iGln-(HHHGWILPVT-)m-Dap) |
a
The difference between the calculated and observed masses of fragment ions.
b
i denotes internal ions.
c
W is modified as HTRP.
d
The y-type ion originating from cleavage of the ether bond between glucosamine and the lactoyl group of N-acetylmuramitol.
e
The y-type ion originating from cleavage of the β-1,4-O-glycosidic bond between glucosamien and N-acetylmuramitol.