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Topic: Constructing an MSP database for MS2 fragmentation (Read 2298 times) previous topic - next topic

Constructing an MSP database for MS2 fragmentation

Dear all,

I am in the process of constructing an MSP database for MS2 fragmentation of common secondary metabolites produced by marine algae. I have been using CFM-ID to generate fragmentation predictions. I am interested in identifying hydrogen, sodium, and ammonium adducts for these compounds. However, I am running into some issues as I proceed with data analysis from seawater samples, so I would like to inquire if my setup for these adducts in my database may be incorrect. Here is an example:

NAME: Pectenotoxin_11_Na
PRECURSORMZ: 897.460
PRECURSORTYPE: [M+H+Na]+
FORMULA: C47H70O15
INCHIKEY: ASJMRRUHURWTNM-YOPFHQOQSA-N
SMILES: CC1CCOC(C1O)(C2C(C3C(O2)C=CC(=CC(CC4(CCC(O4)C56CCC(O5)(CC(O6)C7C(=O)CC(O7)(C(C8CCC9(O8)CCCC(O9)C(C(=O)O3)C)O)C)C)C)C)C)O)O
IONMODE: Positive
Num Peaks: 52
41.0022    5
51.0229    8
53.0386    7
55.0542    18
57.0699    12
59.0855    10
71.0491         13
83.0491    24
85.0648    9
87.0804    7
101.0597   4
103.0754   4
127.039    5
131.0703   4
133.0859   11
191.0914   5
683.379    9
699.3739   6
701.3895   8
713.3895   7
725.3895   14
729.3845   4
731.4001   2
743.4001   7
745.4158   4
843.4525   5
857.4682   12
859.4474   6
875.4787   46
41.0386    5
43.0178    8
43.0542    7
45.0335    18
173.0808   5
715.4052   5
727.3688   6
727.4052   8
801.4056   2
839.4576   7
845.4682   4
847.4838   5
39.0229    5
57.0335    9
59.0491    4
69.0335    5
69.0699    4
73.0648    5
81.0335    9
115.0754   4
129.0546   2
711.3739   7
729.4208   5

Thank you,
Tatiana

 

Re: Constructing an MSP database for MS2 fragmentation

Reply #1
Hi Tatiana,

you should be changed to [M+Na]+ for the sodium adduct information.:)
According to the SMILES code, the exact mass is 874.4714.
Because the precursor m/z is 897.46, it can be expected as [M+Na]+ because the exact mass of Na+ is 22.9892.
Thanks,

Hiroshi