Identification, characterization and determination of metal-binding proteins by liquid chromatography. A review

Abstract

The use of liquid chromatography in the separation and determination of metal-binding proteins is reviewed. Advantages and drawbacks of different chromatographic techniques based on various principles: size exclusion, ion exchange (cationic and ionic), reversed phase and affinity, are presented and discussed. The topic "metal-binding proteins" is considered and presented from two different points of view. The first one regards metal speciation in biological samples (serum and blood). In metal speciation studies, the exact identity of the protein to which the metal is bound often remains unknown. The second point of view is that, frequently, the interest of analyzing metal-binding proteins is not related anymore to the metallic fraction of the protein, but to other chemical structures attached to the protein, such as carbohydrates, which indirectly determine how good the function of the protein is. In this review, special attention is paid to studies dealing with the glycosylation of transferrin, and with the glycated isoform of haemoglobin.

Prediction of Metal Ion–Binding Sites in Proteins Using the Fragment Transformation Method

“…Approximately one-third of all proteins bind at least one metal ion [1], [2], [3], and many different types of metal ion–binding proteins are found in humans [4], [5]. Metal ions help stabilize protein structure, may induce a conformational change upon binding, and/or participate in catalysis.…”

Multielemental Speciation Analysis of Fungi Porcini (Boletus edulis) Mushroom by Size Exclusion Liquid Chromatography with Sequential On-line UV-ICP-MS Detection

“…Size exclusion chromatography (SEC) is a very useful technique to study the distribution of elements in different molecular weight (MW) fractions and gives information about the association of elements with the different sample compounds of various molecular weights ( − ). In the specific case of mushrooms, off-line SEC has been applied for distribution studies of 75 Se and 134 Cs, prior to their determination by using a Ge−Li γ-detector ().…”

MetalloPred: A tool for hierarchical prediction of metal ion binding proteins using cluster of neural networks and sequence derived features

“…The presence of the metal ion allows metalloenzymes to perform functions such as redox reactions that cannot be performed by the limited set of functional groups found in amino acids [1]. Metalloproteins play important roles in structural stability and complex formation [4][5][6][7][8], gene expression regulation and alteration [9][10][11][12], DNA processing [13], signaling processes and cellular event [14], transport [11,15,16], metabolism control [15,17], antibody recognition [18] and other biological processes such as cellular respiration, photosynthesis, nitrogen fixation and antioxidant defense [19]. Approximately, 1/3 of structurally-determined proteins are metalloproteins [20].…”

“…Several sequenced-based computational methods have been explored based on similarity search, metal-binding sites sequence motifs [26,27] and multiple sequence alignments against known metalloproteins [28]. Because of the sequence, structural and functional diversity of metalloproteins [4][5][6][7][8][14][15][16][17], it is desirable to explore additional methods that predict metalloproteins directly from sequence or sequence-derived properties. For a newly-found protein sequence the most interesting thing people wish to know is about its biological function and hence the following questions are often asked: Is the query protein a metalloprotein or non-metalloprotein?…”