質量スペクトロメトリーとガス相赤外線スペクトロスコーピーのガラクトソイドイソマーの区別

Jordan S Ho¹, Amira Gharbi², Baptiste Schindler²

¹Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue Cambridge, Massachusetts 02139, United States.

Journal of the American Chemical Society

|July 8, 2021

まとめ

この研究では,バクテリアのグリカン中の異なる形態のギャラクトースを区別するための新しい質量スペクトロメトリー法が導入されました. この進歩は複雑な細菌の炭水化物を配列化するのに役立ちます

科学分野:

炭水化物の化学
分析化学
グライコバイオロジー

背景:

構造的多様性により,特に様々なモノサッカリドを使用する細菌では,グリカン配列化は困難です.
細菌のグリカンには,哺乳類のグリカンとは異なり,ピラノースの形態と共にガラクトフラノース (Galf) が含まれており,これらの同位体を区別する方法が必要である.

研究の目的:

ピラノースとフーラノースに結合したガラクトースイソマーを区別するための質量スペクトロメトリー-赤外線 (MS-IR) のスペクトロスコピーの方法を開発し,検証する.
異なるアノメリック構成 (α と β) のガラクトーザイソメアのIR指紋を分析する.

主な方法:

質量スペクトロメトリー (MS-IR) と結合した赤外線複数の光子解離 (IRMPD) スペクトロスコーピーを利用した.
ヘクソスアンモニアム添加物を調査し,リチウム添加物とIR指紋を比較した.
開発したMS-IRシグネチャーを galactose リングサイズ割り当てのために分析した.

主要な成果:

MS-IRを用いてピラノースとフラノースに結合したガラクトース残基を成功裏に区別した.
ギャラクトースのピラノースとフラノースの両方のαおよびβアノメアの異なるMS-IRシグネチャを決定した.
これらのシグネチャーの適用性は,ディサカライドのガラクトースリングサイズを決定するために実証されました.

結論:

質量スペクトロメトリー-アンモニア添加物による赤外線スペクトロスコピーは,ギャラクトーザイソメアを区別するのに有効です.
この方法は,バクテリアのグライカンの独特の構造に関する貴重な洞察を提供します.
この発見は,特に複雑な細菌の炭水化物のグリカン配列化の能力を高めています.

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