title: β-Lactoglobulin detected in human milk forms noncovalent complexes with maltooligosaccharides as revealed by chip-nanoelectrospray high-resolution tandem mass spectrometry.
abstract: Cow's milk protein allergy in exclusively breastfed infants, the main cause of food intolerance during the first 6 months of life, is triggered by the mother's diet. β-Lactoglobulin (BLG) present in cow's milk is one of the most potent allergens for newborns. Since no prophylactic treatment is available, finding ligands capable of binding BLG and reducing its allergenicity is currently the focus of research. In this work, an innovative methodology encompassing microfluidics based on fully automated chip-nanoelectrospray ionization (nanoESI), coupled with high-resolution mass spectrometry (MS) on a quadrupole time-of-flight (QTOF MS) instrument was developed. This platform was employed for the assessment of the noncovalent interactions between maltohexaose (Glc6) and β-lactoglobulin extracted from human milk upon deliberate intake of cow's milk. The experiments were carried out in (+) ESI mode, using ammonium acetate (pH 6.0) as the buffer and also in pure water. In both cases, the MS analysis revealed the formation of BLG-Glc6 complex, which was characterized by top-down fragmentation in tandem MS (MS/MS) using collision-induced dissociation (CID). Our findings have a significant biomedical impact, indicating that Glc6 binds BLG under conditions mimicking the in vivo environment and therefore might represent a ligand, able to reduce its allergenicity.
authors.affiliation: Department of Obstetrics, Gynecology and Neonatology, Victor Babes University of Medicine and Pharmacy, Eftimie Murgu Square 2, 300041, Timisoara, Romania.
authors.forename: Florina
authors.initials: F
authors.lastname: Capitan
authors.affiliation: Faculty of Physics, West University of Timisoara, Vasile Parvan Blvd. 4, 300223, Timisoara, Romania.|Mass Spectrometry Laboratory, National Institute for Research and Development in Electrochemistry and Condensed Matter, Plautius Andronescu Str. 1, 300224, Timisoara, Romania.
authors.forename: Adrian C
authors.initials: AC
authors.lastname: Robu
authors.affiliation: Department of Paediatrics, Victor Babes University of Medicine and Pharmacy, Eftimie Murgu Square 2, 300041, Timisoara, Romania.
authors.forename: Catalin
authors.initials: C
authors.lastname: Schiopu
authors.affiliation: Department of Obstetrics, Gynecology and Neonatology, Victor Babes University of Medicine and Pharmacy, Eftimie Murgu Square 2, 300041, Timisoara, Romania.
authors.forename: Constantin
authors.initials: C
authors.lastname: Ilie
authors.affiliation: Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, 1230 York Avenue, New York, NY, 10065-6399, USA.
authors.forename: Brian T
authors.initials: BT
authors.lastname: Chait
authors.affiliation: Department of Chemistry, Laboratory of Analytical Chemistry and Biopolymer Structure Analysis, University of Konstanz, Universitaetsstrasse 10, 78457, Constance, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Przybylski
authors.affiliation: Mass Spectrometry Laboratory, National Institute for Research and Development in Electrochemistry and Condensed Matter, Plautius Andronescu Str. 1, 300224, Timisoara, Romania. alina.zamfir@uav.ro.|Laboratory for the Analysis and Modeling of Biological Systems, Aurel Vlaicu University of Arad, Revolutiei Blvd. 77, 310130, Arad, Romania. alina.zamfir@uav.ro.
authors.forename: Alina D
authors.initials: AD
authors.lastname: Zamfir
mesh_terms: D000818:Animals; D002417:Cattle; D006801:Humans; D007782:Lactoglobulins / Q000032:analysis* / Q000378:metabolism; D008895:Milk, Human / Q000737:chemistry* / Q000378:metabolism; D009844:Oligosaccharides / Q000032:analysis* / Q000378:metabolism; D013045:Species Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D007782:Lactoglobulins; D009844:Oligosaccharides; C021705:maltooligosaccharides
keywords: Human milk; Maltooligosaccharides; Mass spectrometry; Noncovalent interaction; β-Lactoglobulin