Sporothrix schenckii is the etiological agent of sporotrichosis, a subcutaneous mycosis and an emerging disease in immunocompromised patients. Adherence to target cells is a prerequisite for fungal dissemination and systemic complications. However, information on the cell surface components involved in this interaction is rather scarce. In this investigation, the extraction of isolated cell walls from the yeast phase of S. schenckii with SDS and separation of proteins by SDS-PAGE led to the identification of a periodic acid-Schiff (PAS)-reacting 70 kDa glycoprotein (Gp70) that was purified by elution from electrophoresis gels. The purified glycopeptide exhibited a pI of 4.1 and about 5.7% of its molecular mass was contributed by N-linked glycans with no evidence for O-linked oligosaccharides. Confocal analysis of immunofluorescence assays with polyclonal antibodies directed towards Gp70 revealed a rather uniform distribution of the antigen at the cell surface with no distinguishable differences among three different isolates. Localization of Gp70 at the cell surface was confirmed by immunogold staining. Gp70 seems specific for S. schenckii as no immunoreaction was observed in SDS-extracts from other pathogenic and non-pathogenic fungi. Yeast cells of the fungus abundantly adhered to the dermis of mouse tails and the anti-Gp70 serum reduced this process in a concentration-dependent manner. Results are discussed in terms of the potential role of Gp70 in the host-pathogen interaction.

The aims of the study were to evaluate the influence of culture media on biofilm formation byC. albicans, C. glabrata, C. krusei,andC. parapsilosisand to investigate the responses of sessile cells to antifungals and reactive oxygen species (ROS) as compared to planktonic cells. For biofilm formation, theCandidaspecies were grown at different periods of time in YP or YNB media supplemented or not with 0.2 or 2% glucose. Sessile and planktonic cells were exposed to increasing concentrations of antifungals, H₂O₂, menadione or silver nanoparticles (AgNPs). Biofilms were observed by scanning electron microscopy (SEM) and quantified by the XTT assay.C. albicansformed biofilms preferentially in YPD containing 2% glucose (YPD/2%),C. glabratain glucose-free YNB or supplemented with 0.2% glucose (YNB/0.2%), whileC. kruseiandC. parapsilosispreferred YP, YPD/0.2%, and YPD/2%. Interestingly, onlyC. albicansproduced an exopolymeric matrix. This is the first report dealing with thein vitroeffect of the culture medium and glucose on the formation of biofilms in fourCandidaspecies as well as the resistance of sessile cells to antifungals, AgNPs, and ROS. Our results suggest that candidiasisin vivois a multifactorial and complex process where the nutritional conditions, the human immune system, and the adaptability of the pathogen should be considered altogether to provide an effective treatment of the patient.

A soluble α-mannosidase from Candida albicans was purified to homogeneity by sequential size exclusion, ion exchange, and affinity chromatographies in columns of Sepharose CL6B, DEAE Bio-Gel A, and Concanavalin A Sepharose 4B, respectively. Analytical electrophoresis of the purified preparation in 10% SDS–polyacrylamide gels stained with Coomassie blue revealed a single polypeptide of 43 kDa that was responsible for enzyme activity. The purified enzyme primarily trimmed Man₉GlcNAc₂ to produce Man₈GlcNAc₂ isomer B and mannose as a function of time of incubation up to 12 h at 37°C. Prolonged incubation with the enzyme resulted in the accumulation after 24 h of other oligosaccharides corresponding to Man₇GlcNAc₂ and probably Man₆GlcNAc₂. These two products were also observed when Man₈GlcNAc₂ isomer B instead of Man₉GlcNAc₂ was used as substrate. Other oligosaccharides, such as Man₆GlcNAc₂-Asn, Man₅GlcNAc₂-Asn, and the α1,3- and α1,6-linked mannobiosides, were not hydrolyzed at all. These properties are consistent with an α1,2-mannosidase that may represent a new member of the glycosylhydrolase family 47.

Background: Microorganisms produce cell-wall-degrading enzymes as part of their strategies for plant invasion/nutrition. Among these, pectin lyases (PNLs) catalyze the depolymerization of esterified pectin by a β-elimination mechanism. PNLs are grouped together with pectate lyases (PL) in Family 1 of the polysaccharide lyases, as they share a conserved structure in a parallel β-helix. The best-characterized fungal pectin lyases are obtained from saprophytic/opportunistic fungi in the generaAspergillusandPenicilliumand from some pathogens such asColletotrichum gloeosporioides.The organism used in the present study,Colletotrichum lindemuthianum, is a phytopathogenic fungus that can be subdivided into different physiological races with different capacities to infect its host,Phaseolus vulgaris. These include the non-pathogenic and pathogenic strains known as races 0 and 1472, respectively.Results: Here we report the isolation and sequence analysis of theClpnl2gene, which encodes the pectin lyase 2 ofC. lindemuthianum, and its expression in pathogenic and non-pathogenic races ofC. lindemuthianumgrown on different carbon sources. In addition, we performed a phylogenetic analysis of the deduced amino acid sequence of Clpnl2 based on reported sequences of PNLs from other sources and compared the three-dimensional structure of Clpnl2, as predicted by homology modeling, with those of other organisms. Both analyses revealed an early separation of bacterial pectin lyases from those found in fungi and oomycetes. Furthermore, two groups could be distinguished among the enzymes from fungi and oomycetes: one comprising enzymes from mostly saprophytic/opportunistic fungi and the other formed mainly by enzymes from pathogenic fungi and oomycetes. Clpnl2 was found in the latter group and was grouped together with the pectin lyase fromC. gloeosporioides.Conclusions: TheClpnl2gene ofC. lindemuthianumshares the characteristic elements of genes coding for pectin lyases. A time-course analysis revealed significant differences between the two fungal races in terms of the expression ofClpnl2encoding for pectin lyase 2. According to the results, pectin lyases from bacteria and fungi separated early during evolution. Likewise, the enzymes from fungi and oomycetes diverged in accordance with their differing lifestyles. It is possible that the diversity and nature of the assimilatory carbon substrates processed by these organisms played a determinant role in this phenomenon.

The increase in multidrug-resistant organisms worldwide is a major public health threat driven by antibiotic overuse, horizontal gene transfer (HGT), environmental drivers, and deficient infection control in hospitals. In this article, we discuss these factors and summarize the new drugs and treatment strategies suggested to combat the increasing challenges of multidrug-resistant (MDR) bacteria. New treatments recently developed involve targeting key processes involved in bacterial growth, such as riboswitches and proteolysis, and combination therapies to improve efficacy and minimize adverse effects. It also tackles the challenges of the Gram-negative bacterial outer membrane, stressing that novel strategies are needed to evade permeability barriers, efflux pumps, and resistance mechanisms. Other approaches, including phage therapy, AMPs, and AI in drug discovery, are also discussed as potential alternatives. Finally, this review points out the urgency for continued research and development (R&D), industry–academic partnerships, and financial engines to ensure that MDR microbes do not exceed the value of antibacterial therapies.

This review explores current advancements and challenges in antifungal therapies amid rising fungal infections, particularly in immunocompromised patients. We detail the limitations of existing antifungal classes—azoles, echinocandins, polyenes, and flucytosine—in managing systemic infections and the urgent need for alternative solutions. With the increasing incidence of resistance pathogens, such as Candida auris and Aspergillus fumigatus, we assess emerging antifungal agents, including Ibrexafungerp, T-2307, and N′-Phenylhydrazides, which target diverse fungal cell mechanisms. Innovations, such as nanoparticles, drug repurposing, and natural products, are also evaluated for their potential to improve efficacy and reduce resistance. We emphasize the importance of novel approaches to address the growing threat posed by fungal infections, particularly for patients with limited treatment options. Finally, we briefly examine the potential use of artificial intelligence (AI) in the development of new antifungal treatments, diagnoses, and resistance prediction, which provides powerful tools in the fight against fungal pathogens. Overall, we highlight the pressing need for continued research to advance antifungal treatments and improve outcomes for high-risk populations.