Current Protein and Peptide Science - Online First

Mitochondria are organelles in eukaryotic organisms with an electron transport chain consisting of four complexes (i.e., CI, CII, CIII, and CIV) on the inner membrane, which have functions such as providing energy, electron transport, and generating proton gradients. NADH dehydrogenase type 2 (NDH-2), widely found in bacterial, plant, fungal and protist mitochondria, is a nonproton-pumping single-subunit enzyme bound to the surface of the inner mitochondrial membrane that partially replaces NDH-1. NDH-2 has a crucial role in the energy metabolism of pathogenic microorganisms, and the lack of NDH-2 or its homologs in humans makes NDH-2 an essential target for the development of antimicrobial drugs. There is a wide variety of pathogenic microorganisms that invade the human body and cause diseases; therefore, more and more inhibitors targeting NDH-2 of different pathogenic microorganisms continue to be reported. This paper first reviews the structure and function of NDH-2 and summarizes the classification of compounds targeting NDH-2. Given the relative paucity of inhibition mechanisms for NDH-2, which has greatly hindered the development of targeted drugs, the article concludes with a summary of two possible mechanisms in action: allosteric inhibition and competitive inhibition. This review will provide theoretical support for the subsequent molecular design and modification of drugs targeting the pathogenic microorganism NDH-2.

A special kind of posttranslational process known as proteolytic cleavage controls the half-lives and functions of several extracellular and intracellular proteins. The metalloproteinase ADAM10 has attracted attention because it cleaves a growing amount of protein substrates close to the extracellular membrane leaflet. The process known as “ectodomain shedding” controls the turnover of certain transmembrane proteins that are essential for receptor signaling and cell adhesion. It may trigger nuclear transport, intramembrane proteolysis, and cytoplasmic domain signaling. Additional human illnesses linked to ADAM10 include cancer, immune system malfunction, and neurodegeneration. The difficulty in targeting proteases for medicinal reasons stems from the many substrates that these enzymes, particularly ADAM10, have. It is usually necessary to precisely identify the therapeutic beneficial window of use since blocking or accelerating a particular protease activity is linked with undesirable side effects. More knowledge of the regulatory pathways governing ADAM10 expression, subcellular localization, and activity will probably lead to the identification of viable therapeutic targets, enabling more targeted and precise manipulation of the enzyme's proteolytic activity.

Neoplastic transformation of B cells of the post-germinative center can lead to oncohematological dyscrasias, which often results in an abnormal production of monoclonal immunoglobulin light chains. The non-physiological production of large amounts of IgG light chains leads to the formation of extracellular deposits called 'aggregomas' and rare conditions such as light chain crystal deposition disease. Kidney manifestations and heavy-chain deposition disease can also occur in plasma cell dyscrasias, emphasizing the role of IgG misfolding and aggregation. This minireview describes molecular mechanisms of IgG light-chain aggregation, as well as the consequences and therapeutic implications of IgG light chain misfolding in these disorders. By elucidating the mechanisms of IgG light chain misfolding and aggregation, researchers can identify specific molecular and cellular pathways. This knowledge opens the door to novel therapeutic targets, offering the potential for interventions that can either prevent the initial misfolding events, promote the proper folding and processing of immunoglobulins, or enhance the clearance of misfolded proteins and aggregates. These protein folding-related issues persist even after the successful elimination of the malignant B cells. Such targeted protein-folding therapies could significantly improve patients' quality of life and contribute to their recovery. Thus, a deep understanding of IgG light chain misfolding and its consequences not only sheds light on the complex biology of oncohematological dyscrasias but also opens the way for innovative treatment strategies that could transform patient care in these conditions, instilling hope and motivation in the healthcare professionals and researchers in this field.