Corn head smut is a disease caused by the fungus Sporisorium reilianum . This phytosanitary problem has existed for several decades in the Mezquital Valley, an important corn-producing area in central Mexico. To combat the problem, a strain identified as Bacillus subtilis 160 was applied in the field, where it decreased disease incidence and increased crop productivity. In this study, the sequencing and analysis of the whole genome sequence of this strain were carried out to identify its genetic determinants for the production of antimicrobials. The B. subtilis 160 strain was found to be Bacillus velezensis . Its genome has a size of 4,297,348 bp, a GC content of 45.8%, and 4,174 coding sequences. Comparative analysis with the genomes of four other B. velezensis strains showed that they share 2,804 genes and clusters for the production of difficidin, bacillibactin, bacilysin, macrolantin, bacillaene, fengycin, butirosin A, locillomycin, and surfactin. For the latter metabolite, unlike the other strains that have only one cluster, B. velezensis 160 has three. A cluster for synthesizing laterocidine, an antimicrobial reported only in Brevibacillus laterosporus , was also identified. IMPORTANCE: In this study, we performed sequencing and analysis of the complete genome of the strain initially identified as Bacillus subtilis 160 as part of its characterization. This bacterium has shown its ability to control corn head smut in the field, a disease caused by the basidiomycete fungus Sporisorium reilianum . Analyzing the complete genome sequence not only provides a more precise taxonomic identification but also sheds light on the genetic potential of this bacterium, especially regarding mechanisms that allow it to exert biological control. Employing molecular and bioinformatics tools in studying the genomes of agriculturally significant microorganisms offers insights into the development of biofungicides and bioinoculants. These innovations aim to enhance plant growth and pave the way for strategies that boost crop productivity.

In this paper, the amino acid sequence of the β-xylanase SRXL1 of Sporisorium reilianum, which is a pathogenic fungus of maize was used as a model protein to find its phylogenetic relationship with other xylanases of Ascomycetes and Basidiomycetes and the information obtained allowed to establish a hypothesis of monophyly and of biological role. 84 amino acid sequences of β-xylanase obtained from the GenBank database was used. Groupings analysis of higher-level in the Pfam database allowed to determine that the proteins under study were classified into the GH10 and GH11 families, based on the regions of highly conserved amino acids, 233–318 and 180–193 respectively, where glutamate residues are responsible for the catalysis.

Sposisorium reilianum is the causal agent of corn ear smut disease. Eleven genes have been identified in its genome that code for enzymes that could constitute its hemicellulosic system, three of which have been associated with two Endo-β-1,4-xylanases and one with α-L-arabinofuranosidase activity. In this study, the native protein extracellular with β-xylosidase activity, called SRBX1, produced by this basidiomycete was analyzed by performing production kinetics and its subsequent purification by gel filtration. The enzyme was characterized biochemically and sequenced. Finally, its synergism with Xylanase SRXL1 was determined. Its activity was higher in a medium with corn hemicellulose and glucose as carbon sources. The purified protein was a monomer associated with the sr16700 gene, with a molecular weight of 117 kDa and optimal activity at 60 °C in a pH range of 4–7, which had the ability to hydrolyze the ρ-nitrophenyl β-D-xylanopyranoside and ρ-Nitrophenyl α-L-arabinofuranoside substrates. Its activity was strongly inhibited by silver ions and presented Km and Vmax values of 2.5 mM and 0.2 μmol/min/mg, respectively, using ρ-nitrophenyl β-D-xylanopyranoside as a substrate. The enzyme degrades corn hemicellulose and birch xylan in combination and in sequential synergism with the xylanase SRXL1.

The natural compounds PSK and PSP have antitumor and immunostimulant properties. These pharmacological benefits have been documented in vitro and in vivo, although there is no information in silico which describes the action mechanisms at the molecular level. In this study, the inverse docking method was used to identify the interactions of PSK and PSP with two local databases: BPAT with 66 antitumor proteins, and BPSIC with 138 surfaces and intracellular proteins. This led to the identification interactions and similarities of PSK and the AB680 inhibitor in the active site of CD73. It was also found that PSK binds to CD59, interacting with the amino acids APS22 and PHE23, which coincide with the rlLYd4 internalization inhibitor. With the isoform of the K-RAS protein, PSK bonded to the TYR32 amino acid at switch 1, while with BAK it bonded to the region of the α1 helix, while PSP bonded to the activation site and the C-terminal and N-terminal ends of that helix. In Bcl-2, PSK interacted at the binding site of the Venetoclax inhibitor, showing similarities with the amino acids ASP111, VAL133, LEU137, MET115, PHE112, and TYR108, while PSP had similarities with THR132, VAL133, LEU137, GLN118, MET115, APS111, PHE112, and PHE104.

Head smut in maize (Zea mays) is a systemic disease caused by the phytopathogenic fungus Sporisorium reilianum. One of the most severely affected regions in Mexico is Valle del Mezquital in the state of Hidalgo, a high production zone with irrigated agriculture that produces over 50% of maize supplies in the state. This study was designed to analyze the genetic diversity of this phytopathogen isolated from different zones of Valle del Mezquital using the following molecular markers: ITS, aspartyl protease, β-tubulin, and the mitochondrial endonuclease LAGLIDADG. Our objective was to estimate the level of genetic variability in a regional space and understand the evolutionary processes to which non-model organisms are subjected. A total of 53 strains of S. reilianum were isolated from the sampling sites and then purified. A Bayesian Analysis of Population Structure (BAPS) analysis of the genetic structuring allowed us to recover three genetic groupings (K = 3), while molecular variance analysis (AMOVA) showed a very low fixation index (F_ST = 0.0146), which was not statistically significant and indicated little between-group genetic differentiation. Also, the value determined for the coefficient of genetic differentiation (Gst) showed little variation among the genetic groups, while the gene flow number (Nm) was 8.25. The Tajima’s D estimator and haplotype network recently indicated a rapid population expansion. Together, these results suggest that reproduction and migration are key factors in the evolution and virulence of this fungus.

Botrytis cinerea is the causal agent of gray mold, a disease that attacks many plants worldwide. This phytosanitary problem was reported in orchards in the State of Mexico, Mexico, specifically in pomegranate crops. This study isolated this phytopathogen from fruits collected in the municipality of Chilcuautla, state of Hidalgo, Mexico, indicating that the disease is spreading across the country. Two strains of phytopathogens, MIC and MID, were obtained after conducting Koch’s postulates. These strains were identified molecularly by amplifying and analyzing the concatenated sequence of the regions that correspond to the internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (G3PDH), and DNA-dependent RNA polymerase subunit II (RPB2). In vitro confrontation tests demonstrated that Bacillus velezensis 160 inhibited the development of both strains of B. cinerea under study through the action of nonvolatile, thermostable, and volatile metabolites. Applying this bacterium to pomegranate orchards for two consecutive years (2022 and 2023) decreased the incidence, severity, and progression of the disease. We conclude that this bacterium can be used as a fungicide to control gray mold in pomegranate crops. [ ] Copyright © 2025 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .