Bacterial collagenases are metalloproteinases involved in the degradation of the extracellular matrices of animal cells, due to their ability to digest native collagen. These enzymes are important virulence factors in a variety of pathogenic bacteria. Nonetheless, there is a lack of scientific consensus for a proper and well-defined classification of these enzymes and a vast controversy regarding the correct identification of collagenases. Clostridial collagenases were the first ones to be identified and characterized and are the reference enzymes for comparison of newly discovered collagenolytic enzymes. In this review we present the most recent data regarding bacterial collagenases and overview the functional and structural diversity of bacterial collagenases. An overall picture of the molecular diversity and distribution of these proteins in nature will also be given. Particular aspects of the different proteolytic activities will be contextualized within relevant areas of application, mainly biotechnological processes and therapeutic uses. At last, we will present a new classification guide for bacterial collagenases that will allow the correct and straightforward classification of these enzymes.

Marine fungi play a crucial role in energy flow and nutrient recycling, mediating the cycling of dissolved organic matter in marine environments. However, despite being a prolific group of organisms, marine fungi have been largely neglected for a long time. Besides their importance in the marine food web, marine fungi represent an active source of natural products. Over the last years, researchers have focused on studying marine organisms to discover new metabolites with antibacterial, antiviral, and anticancer activities. Moreover, with the advances in high-throughput sequencing technologies and mass spectrometry techniques, genomic and metabolomic approaches have revealed to be of paramount importance in natural products discovery. The marine mycobiome includes many organisms still to be identified, and the ones already known are still underutilized in biotechnological applications. For this reason, it is undeniable that exploring the marine mycobiome including new habitats and substrates, even those of remote access, is fundamental for describing the true magnitude of the Earth’s mycobiome.

Lasiodiplodia theobromae (Botryosphaeriaceae, Ascomycota) is a plant pathogen and human opportunist whose pathogenicity is modulated by temperature. The molecular effects of temperature on L. theobromae are mostly unknown, so we used a multi-omics approach to understand how temperature affects the molecular mechanisms of pathogenicity. The genome of L. theobromae LA-SOL3 was sequenced (Illumina MiSeq) and annotated. Furthermore, the transcriptome (Illumina TruSeq) and proteome (Orbitrap LC-MS/MS) of LA-SOL3 grown at 25 °C and 37 °C were analysed. Proteins related to pathogenicity (plant cell wall degradation, toxin synthesis, mitogen-activated kinases pathway and proteins involved in the velvet complex) were more abundant when the fungus grew at 25 °C. At 37 °C, proteins related to pathogenicity were less abundant than at 25 °C, while proteins related to cell wall organisation were more abundant. On the other hand, virulence factors involved in human pathogenesis, such as the SSD1 virulence protein, were expressed only at 37 °C. Taken together, our results showed that this species presents a typical phytopathogenic molecular profile that is compatible with a hemibiotrophic lifestyle. We showed that L. theobromae is equipped with the pathogenesis toolbox that enables it to infect not only plants but also animals.

Phytopathogenic fungi are known for producing an arsenal of extracellular enzymes whose involvement in the infection mechanism has been suggested. However, these enzymes are largely unknown and their biotechnological potential also remains poorly understood. In this study, the production and thermostability of extracellular enzymes produced by phytopathogenic Botryosphaeriaceae was investigated. Hydrolytic and oxidative activities were detected and quantified at different temperatures. Most strains (70%; 37/53) were able to produce simultaneously cellulases, laccases, xylanases, pectinases, pectin lyases, amylases, lipases, and proteases. Surprisingly for mesophilic filamentous fungi, several enzymes proved to be thermostable: cellulases from Neofusicoccum mediterraneum CAA 001 and from Dothiorella prunicola CBS 124723, lipases from Diplodia pinea (CAA 015 and CBS 109726), and proteases from Melanops tulasnei CBS 116806 were more active at 70 °C than at any of the other temperatures tested. In addition, lipases produced by Diplodia pinea were found to be significantly more active than any other known lipase from Botryosphaeriales. The thermal activity profile and the wide array of activities secreted by these fungi make them optimal producers of biotechnologically relevant enzymes that may be applied in the food and the health industries (proteases), the pulp-and-paper and biofuel industries (cellulases), or even in the detergent industry (lipases, proteases, amylases, and cellulases).