International Journal of Molecular Sciences

Journal Browser

► Journal Browser

Special Issue Editor

Special Issue Information

Dear Colleagues,

Current trends in physicochemical biology and the search for new solutions to problems in biotechnology and medicine require more detailed information about the structure of such biopolymers as proteins and polysaccharides, as well as their complexes. In addition to their individual functions in living systems, proteins and polysaccharides are involved in the formation of supramolecular structures that carry a specific structural and functional load. Fundamental studies of intermolecular interactions of biological macromolecules and the formation of functional supramolecular complexes on their basis are an integral part of modern molecular biophysics. In terms of the variety of controlled properties, composite systems based on proteins and polysaccharides have great prospects. Due to their unique structural properties, including tunable physical, chemical, and biological characteristics, and good biocompatibility, protein-polysaccharide systems are promising materials in medicine and pharmacology. However, as in fundamental physical and chemical biology, in biotechnology, clear qualitative and quantitative information about the structure and other biophysical characteristics of biological macromolecules and supramolecular systems based on them are of great importance. Potential topics include, but are not limited to:

Proteins and polysaccharides complexation;
Supramolecular protein-polysaccharide structures;
Composite systems based on proteins and polysaccharides;
Biophysical characteristics of protein-polysaccharide supramolecular systems;
Immobilization of enzyme on polysaccharides;
Protein–polysaccharide systems are promising materials in medicine and pharmacology.

Dr. Marina Holyavka
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. International Journal of Molecular Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. There is an Article Processing Charge (APC) for publication in this open access journal. For details about the APC please see here. Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

protein-polysaccharide complexes
structure
physico-chemical properties
supramolecular systems
immobilization

Published Papers (2 papers)

Download All Papers

Research

12 pages, 4822 KiB

Open AccessArticle

Sulfated Polysaccharides as a Fighter with Protein Non-Physiological Aggregation: The Role of Polysaccharide Flexibility and Charge Density

by Olga N. Makshakova, Liliya R. Bogdanova, Dzhigangir A. Faizullin, Elena A. Ermakova and Yuriy F. Zuev

Int. J. Mol. Sci. 2023, 24(22), 16223; https://doi.org/10.3390/ijms242216223 - 12 Nov 2023

Viewed by 909

Abstract

Proteins can lose native functionality due to non-physiological aggregation. In this work, we have shown the power of sulfated polysaccharides as a natural assistant to restore damaged protein structures. Protein aggregates enriched by cross-β structures are a characteristic of amyloid fibrils related to different health disorders. Our recent studies demonstrated that model fibrils of hen egg white lysozyme (HEWL) can be disaggregated and renatured by some negatively charged polysaccharides. In the current work, using the same model protein system and FTIR spectroscopy, we studied the role of conformation and charge distribution along the polysaccharide chain in the protein secondary structure conversion. The effects of three carrageenans (κ, ι, and λ) possessing from one to three sulfate groups per disaccharide unit were shown to be different. κ-Carrageenan was able to fully eliminate cross-β structures and complete the renaturation process. ι-Carrageenan only initiated the formation of native-like β-structures in HEWL, retaining most of the cross-β structures. In contrast, λ-carrageenan even increased the content of amyloid cross-β structures. Furthermore, κ-carrageenan in rigid helical conformation loses its capability to restore protein native structures, largely increasing the amount of amyloid cross-β structures. Our findings create a platform for the design of novel natural chaperons to counteract protein unfolding. Full article

(This article belongs to the Special Issue Protein-Polysaccharide Complexes: Structure and Physico-Chemical Properties)

► Show Figures

Figure 1

16 pages, 3209 KiB

Open AccessArticle

Influence of pH on Inulin Conversion to 2,3-Butanediol by Bacillus licheniformis 24: A Gene Expression Assay

by Lidia Tsigoriyna, Alexander Arsov, Emanoel Gergov, Penka Petrova and Kaloyan Petrov

Int. J. Mol. Sci. 2023, 24(18), 14065; https://doi.org/10.3390/ijms241814065 - 14 Sep 2023

Viewed by 867

Abstract

2,3-Butanediol (2,3-BD) is an alcohol highly demanded in the chemical, pharmaceutical, and food industries. Its microbial production, safe non-pathogenic producer strains, and suitable substrates have been avidly sought in recent years. The present study investigated 2,3-BD synthesis by the GRAS Bacillus licheniformis 24 using chicory inulin as a cheap and renewable substrate. The process appears to be pH-dependent. At pH 5.25, the synthesis of 2,3-BD was barely detectable due to the lack of inulin hydrolysis. At pH 6.25, 2,3-BD concentration reached 67.5 g/L with rapid hydrolysis of the substrate but was accompanied by exopolysaccharide (EPS) synthesis. Since inulin conversion by bacteria is a complex process and begins with its hydrolysis, the question of the acting enzymes arose. Genome mining revealed that several glycoside hydrolase (GH) enzymes from different CAZy families are involved. Five genes encoding such enzymes in B. licheniformis 24 were amplified and sequenced: sacA, sacB, sacC, levB, and fruA. Real-time RT-PCR experiments showed that the process of inulin hydrolysis is regulated at the level of gene expression, as four genes were significantly overexpressed at pH 6.25. In contrast, the expression of levB remained at the same level at the different pH values at all-time points. It was concluded that the sacC and sacA/fruA genes are crucial for inulin hydrolysis. They encode exoinulinase (EC 3.2.1.80) and sucrases (EC 3.2.1.26), respectively. The striking overexpression of sacB under these conditions led to increased synthesis of EPS; therefore, the simultaneous production of 2,3-BD and EPS cannot be avoided. Full article

(This article belongs to the Special Issue Protein-Polysaccharide Complexes: Structure and Physico-Chemical Properties)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Protein-Polysaccharide Complexes: Structure and Physico-Chemical Properties

Share This Special Issue

Special Issue Editor

Special Issue Information

Keywords

Published Papers (2 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI