Structural studies in nucleic acid chemistry by mass spectrometry

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1992

OSTI ID:7112924

Phillips, D R

This dissertation is composed of three major topics: the structure determination, principally by mass spectrometry, of a new nucleotide antibiotic, phosmidosine; a comparative study of high and low energy collision-induced dissociation (CID) of dinucleoside monophophate ions; and the results of which are applied to the identification of 2'-O-methylribonucleotidylyl ribonucleosides formed by ribonuclease T[sub 2] digestion of tRNA. The structure determination of phosmidosine was complicated by chemical instability and the presence of impurities in the isolate. The necessity of isolating the phosmidosine was circumvented by using tandem mass spectrometry (MS/MS), and liquid chromatography-mass spectrometry (LC/MS). The majority of MS/MS experiments were performed on the isopropylidene derivative because of increased sample ion abundance from fast atom bombardment (FAB). The structure of the nucleoside, produced from phosmidosine by base hydrolysis, was confirmed by comparing LC/MS and gas chromotography-mass spectrometry data to that of synthetic 8-hydroxyadenosine. The phosmidosine isolate also contained two homologs and an isomer that were characterized. Low energy CID were obtained for all common heterodinucleoside monophosphates and three 2'-O-methylribonucleotidylyl ribonucleosides. A dinucleoside monophosphate sequence could be determined by comparing nucleoside base ion peak heights in the CID mass spectra of (M-H)[sup [minus]], and ion m/z 81 (C[sub 5]H[sub 5]O[sup +]) from deoxyribo- or m/z 97 (C[sub 5]H[sub 5]O[sub 2][sup +]) from ribondinucleoside monophosphates is observed in all CID mass spectra of MH[sup +] from dinucleoside monophosphates. 2'-O-Methylribonucleotidylyl ribonucleosides found in RNase T[sub 2] digested RNA can be identified directly from the digest by using precursor ion scans of m/z 97, and product ion mass spectra provided conformation and sequence information.

• Research Organization: Utah State Univ., Logan, UT (United States)
• OSTI ID: 7112924
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
ANTI-INFECTIVE AGENTS
ANTIBIOTICS
CHROMATOGRAPHY
DRUGS
LIQUID COLUMN CHROMATOGRAPHY
MASS SPECTRA
NUCLEOTIDES
ORGANIC COMPOUNDS
SEPARATION PROCESSES
SPECTRA
STRUCTURAL CHEMICAL ANALYSIS