TY - JOUR
T1 - Characterization of Hydroxyphthioceranoic and Phthioceranoic Acids by Charge-Switch Derivatization and CID Tandem Mass Spectrometry
AU - Hsu, Fong Fu
N1 - Publisher Copyright:
© American Society for Mass Spectrometry 2016.
PY - 2016/4
Y1 - 2016/4
N2 - Hydroxyphthioceranoic (HPA) and phthioceranoic (PA) acids are polymethylated long chain fatty acids with and without a hydroxyl group attached to the carbon next to the terminal methyl-branched carbon distal to the carboxylic end of the long-chain fatty acid, respectively. They are the major components of the sulfolipids found in the cell wall of Mycobacterium tuberculosis (M. tuberculosis) strain H37Rv. In this report, I describe CID linear ion-trap MSn mass spectrometric approaches combined with charge-reverse derivatization strategy toward characterization of these complex lipids, which were released from sulfolipids by alkaline hydrolysis and sequentially derivatized to the N-(4-aminomethylphenyl) pyridinium (AMPP) derivatives. This method affords complete characterization of HPA and PA, including the location of the hydroxyl group and the multiple methyl side chains. The study also led to the notion that the hydroxyphthioceranoic acid in sulfolipid consists of two (for hC24) to 12 (for hC52) methyl branches, and among them 2,4,6,8,10,12,14,16-octamethyl-17-hydroxydotriacontanoic acid (hC40) is the most prominent, while phthioceranoic acids are the minor constituents. These results confirm our previous findings that sulfolipid II, a family of homologous 2-stearoyl(palmitoyl)-3,6,6′-tris(hydroxyphthioceranoy1)-trehalose 2′-sulfates is the predominant species, and sulfolipid I, a family of homologous 2-stearoyl(palmitoyl)-3-phthioceranoyl-6,6′-bis(hydroxyphthioceranoy1)-trehalose 2′-sulfates is the minor species in the cell wall of M. tuberculosis.
AB - Hydroxyphthioceranoic (HPA) and phthioceranoic (PA) acids are polymethylated long chain fatty acids with and without a hydroxyl group attached to the carbon next to the terminal methyl-branched carbon distal to the carboxylic end of the long-chain fatty acid, respectively. They are the major components of the sulfolipids found in the cell wall of Mycobacterium tuberculosis (M. tuberculosis) strain H37Rv. In this report, I describe CID linear ion-trap MSn mass spectrometric approaches combined with charge-reverse derivatization strategy toward characterization of these complex lipids, which were released from sulfolipids by alkaline hydrolysis and sequentially derivatized to the N-(4-aminomethylphenyl) pyridinium (AMPP) derivatives. This method affords complete characterization of HPA and PA, including the location of the hydroxyl group and the multiple methyl side chains. The study also led to the notion that the hydroxyphthioceranoic acid in sulfolipid consists of two (for hC24) to 12 (for hC52) methyl branches, and among them 2,4,6,8,10,12,14,16-octamethyl-17-hydroxydotriacontanoic acid (hC40) is the most prominent, while phthioceranoic acids are the minor constituents. These results confirm our previous findings that sulfolipid II, a family of homologous 2-stearoyl(palmitoyl)-3,6,6′-tris(hydroxyphthioceranoy1)-trehalose 2′-sulfates is the predominant species, and sulfolipid I, a family of homologous 2-stearoyl(palmitoyl)-3-phthioceranoyl-6,6′-bis(hydroxyphthioceranoy1)-trehalose 2′-sulfates is the minor species in the cell wall of M. tuberculosis.
KW - Charge reversed derivatization
KW - Charge-remote fragmentation
KW - HCD
KW - Linear ion-trap
KW - Lipidomics
KW - Microbial lipids
KW - Mycobacterium tuberculosis
UR - http://www.scopus.com/inward/record.url?scp=84962270565&partnerID=8YFLogxK
U2 - 10.1007/s13361-015-1328-2
DO - 10.1007/s13361-015-1328-2
M3 - Article
C2 - 26729458
AN - SCOPUS:84962270565
SN - 1044-0305
VL - 27
SP - 622
EP - 632
JO - Journal of the American Society for Mass Spectrometry
JF - Journal of the American Society for Mass Spectrometry
IS - 4
ER -