Poliseli Camila B, Tonin Angelica P P, Martinez Fernanda C, Nascimento Nicholas C do, Braz Vilmar, Maluf Jose, Ribeiro Valquiria M S, Della Rosa Fernanda A, Souza Gustavo H M F, Meurer Eduardo C
Campus Avançado Jandaia do Sul, Universidade Federal do Paraná (UFPR), 86900-000, Jandaia do Sul, Brazil.
Departamento de Química, Universidade Estadual de Maringá (UEM), Av. Colombo, 5790, 87020-900, Maringá, Brazil.
J Mass Spectrom. 2021 Feb;56(2):e4701. doi: 10.1002/jms.4701.
We describe a fast (5 min) liquid chromatography tandem mass spectrometry method (LC-MS/MS) based on a 46 Da neutral loss of formic acid (H O and CO) to identify tri- and dipeptides (DIPEP) in whey protein and porcine liver protein hydrolysates and confirmed by further de novo sequencing. Sample solutions were acidified to favor [dipep + H] ions, and a m/z range of 50-300 was used to improve sensitivity. All dipeptide candidates were selected based on all possibilities of the 20 amino acid combinations, and their collision-induced dissociation fragments were screened via de novo sequencing. To determine their biological activities, sequenced dipeptides were compared with the Biopep database and other data from literature. Altogether, 18 dipeptides and 7 tripeptides were identified from the whey protein hydrolysate; they seemed to be broadly active, and peptides were identified as active dipeptidyl peptidase IV inhibitors and active angiotensin-converting enzyme (ACE), according to available information. Porcine liver hydrolysate showed 14 dipeptides which exhibit similar biological activities to whey protein hydrolysate.
我们描述了一种快速（5分钟）的液相色谱串联质谱法（LC-MS/MS），该方法基于46 Da的甲酸中性丢失（H₂O和CO）来鉴定乳清蛋白和猪肝蛋白水解物中的三肽和二肽（DIPEP），并通过进一步的从头测序进行确认。将样品溶液酸化以促进[二肽 + H]⁺离子的形成，并使用50 - 300的m/z范围来提高灵敏度。所有二肽候选物均基于20种氨基酸组合的所有可能性进行选择，并通过从头测序筛选其碰撞诱导解离片段。为了确定它们的生物活性，将测序的二肽与Biopep数据库以及文献中的其他数据进行比较。从乳清蛋白水解物中总共鉴定出18种二肽和7种三肽；它们似乎具有广泛的活性，根据现有信息，这些肽被鉴定为活性二肽基肽酶IV抑制剂和活性血管紧张素转换酶（ACE）。猪肝水解物显示出14种二肽，其具有与乳清蛋白水解物相似的生物活性。
