Table 1 of Peterson, Mol Vis 2004; 10:857-866.

Table 1. Sequences assigned to experimental m/z for tryptic peptides

Summary of sequences assigned to experimental mass to charge ratios (m/z) for tryptic peptides based on sequencing data or mass correlation. Experimental masses from different cross-linking reactions were compared across each row to search for structures that were equivalent apart from the structure of the cross-linker. Rows with more than one experimental mass have structures from different cross-linking experiments that are correlated. Note three different changes in mass (Δm=+12, +24, or +42) were considered as a result of cross-linking and/or modification by formaldehyde [32]. If no correlated ion was found within 200 ppm of the theoretical m/z for the modification, the designation "NO" (Not observed) was entered. Measured m/z for product ions resulting from the different reagent treatments are shown in black font. Theoretical m/z of these ions are shown in red. Ion charges greater than one are reported in parenthesis. Numbered lysines denote confirmed or possible sites of modification by formaldehyde (FA) or DTSSP. The sharp (hash mark) indicates that the singly deamidated species was also observed at a different retention time and sequenced. Its mass is not listed. The single asterisk indicates that these ions have been sequenced using collision induced decay (CID). The double asterisk indicates that no correlation was observed, but loss of Ac-Met and extensive loss of Arg was observed. The triple asterisk indicates that the deamidated species was observed. The "at" symbol (@) indicates oxidation of methionine was observed. Conclusions derived from each deduced product are listed in the final column.

   Name                  Sequence                  DTSSP       Δm=+12.00    Δm=+24.00   Δm=+42.01       Conclusion
----------   --------------------------------   -----------   -----------   ---------   ---------   -------------------
αA1-12*#     Ac-MDIAIQHPWFK11R                  1775.8        1596.1        NO          NO          K11 of αA solvent
                                                1775.82       1595.82                               accessible

αA71-88*     FVIFLDVK78HFSPEDLTVK               2326.2        NO            NO          NO          K78 of αA solvent
                                                2326.17                                             accessible

αA89-103*#   VQEDFVEIHGK99HNER                  2027.9        NO            NO          NO          K99 of αA solvent
                                                2027.9                                              accessible

αB164-175    EEK166PAVTAAPK174K                 1460.9        NO            NO          1310.9      K166 or K174 of αB
                                                1460.73                                 1310.73     solvent accessible

α164-175     EEK166PAVTAAPK174K                 1442.9        NO            NO          1310.9      K166 and K174 of αB
             (Intrapeptide crosslink)           1442.72                                 1310.73     solvent accessible

αB70-74      LEK72DR-APSWIDTGLSEMRLEK72DR       1469.0  (2)   1396.0 (2)@   NO          NO          K72 of αB involved
αB57-74                                         1469.21 (2)   1396.21 (2)                           in αB-αB subunit

αB70-74      LEK72DR-LEK72DRFSVNLDVK            1198.8  (2)   2235.2***     NO          NO          K72 of αB involved
αB70-82                                         1198.61 (2)   2234.21                               in αB-αB subunit

αB150-157    K150QASGPER-TIPITREEK166PAVTAAPK   1434.5  (2)   1353.4 (2)    NO          NO          K150 and K166 of αB
αB158-174                                       1434.25 (2)   1353.25 (2)                           involved in
                                                                                                    crosslinking or
                                                                                                    αB-αB subunit

αB117-123    EFHRK121YR-VQEDFVEIHGK99HNER       1523.6  (2)   1442.0 (2)    NO          NO          K121 of αB and K99
αA89-103                                        1523.22 (2)   1442.22 (2)                           of αA involved in
                                                                                                    αB-αA interactions

αB117-123    EFHRK121YR-Ac-MDIAIEHPWFK11R       NO            NO            2643.17**   NO          K121 of αB and K11
αA1-12**                                                                    2642.35                 of αA involved in
                                                                                                    αB-αA interactions

Peterson, Mol Vis 2004; 10:857-866 <>
©2004 Molecular Vision <>
ISSN 1090-0535