Vidushi Abrol

In this study, we employed liquid chromatography-tandem mass spectrometry (LC-MS/MS) to perform chemo-profiling on four fungal species: three Trichoderma species─two strains of Trichoderma asperellum (S3-3 and S3-1) and one Trichoderma longibrachiatum (FS-46)─and one species from the Tolypocladium genus, Tolypocladium inflatum (MTCC-3538). Our analysis identified 78 peptaibols featuring α-aminoisobutyric acid (Aib). Among these, we discovered both cyclic and linear Peptaibols and lipopeptaibols with Aib, ranging in putative molecular weights from 1033.4 to 1953.6 g/mol, corresponding to peptide lengths of 10-20 amino acids. In total, 78 peptaibols, including lipopeptaibols, were identified through LC-MS/MS. Of these, 43 were recognized as new peptaibols based on mass fragmentation patterns and sequence data from the MS/MS analysis. Our findings suggest that LC-MS/MS-based large-scale studies of the peptaibiome will enable the discovery of novel peptaibols and provide a valuable reference for understanding fragmentation patterns of peptaibols, cyclic peptaibols, and lipopeptaibols. Moreover, LC-MS/MS allows rapid identification of peptaibiotics at low concentrations directly in extracts, offering a potential quality control method for selecting beneficial Trichoderma strains for crop protection, while their fragmentation patterns and plausible sequences can guide synthetic design.

In this study, we employed liquid chromatography–tandem mass spectrometry (LC–MS/MS) to perform chemo-profiling on four fungal species: three Trichoderma species—two strains of Trichoderma asperellum (S3-3 and S3-1) and one Trichoderma longibrachiatum (FS-46)—and one species from the Tolypocladium genus, Tolypocladium inflatum (MTCC-3538). Our analysis identified 78 peptaibols featuring α-aminoisobutyric acid (Aib). Among these, we discovered both cyclic and linear Peptaibols and lipopeptaibols with Aib, ranging in putative molecular weights from 1033.4 to 1953.6 g/mol, corresponding to peptide lengths of 10-20 amino acids. In total, 78 peptaibols, including lipopeptaibols, were identified through LC-MS/MS. Of these, 43 were recognized as new peptaibols based on mass fragmentation patterns and sequence data from the MS/MS analysis. Our findings suggest that LC-MS/MS-based large-scale studies of the peptaibiome will facilitate the discovery of novel peptaibols and provide a valuable reference for understanding the fragmentation patterns of peptaibols, cyclic peptaibols, and lipopeptaibols.

In the present study, a series of benzotriazole-based β-amino alcohols were efficiently synthesized in excellent yields via aminolysis of benzotriazolated epoxides under catalyst- and solvent-free conditions. Further these β-amino alcohols were successfully utilized to synthesize the corresponding benzotriazole-based oxazolidine heterocyclic derivatives. All the synthesized compounds were characterized by various spectroscopic techniques such as ¹H NMR, ¹³C NMR, and mass spectroscopy for structure elucidation. The compounds were subjected to a microtiter plate-based antimicrobial assay. The antimicrobial activity results reveal that the compounds 4a, 4e, and 5f were found to be active against Staphylococcus aureus (ATCC-25923) with minimum inhibitory concentrations (MICs) of 32, 8, and 64 μM, respectively. Also, the compounds 4a, 4e, 4k, 4i, 4m, 4n, 4o, 5d, 5e, 5f, 5g, and 5h showed effective activity against Bacillus subtilis (ATCC 6633) with MICs of 64, 16, 16, 16, 64, 16, 64, 64, 32, 64, 8, and 16 μM, respectively. A biological investigation was conducted, including molecular docking of two compounds with several receptors to identify and confirm the best ligand-protein interactions. Hence, this study found a significant strategy to diversify the chemical molecules. The synthesized compounds play a potential role as an antibacterial intensifier against some pathogenic bacteria for the development of antibacterial substances.

[This corrects the article DOI: 10.1021/acsomega.2c03037.].

The Rosellinia sanctae-cruciana extract was subjected to detailed liquid chromatography tandem mass spectrometry studies. A total of 38 peaks were annotated to m/z 508.26, m/z 510.28, m/z 524.26, m/z 526.28, m/z 540.26, m/z 542.27, and m/z 584.28 [M + H]⁺. The accurate mass, mutually supported UV/vis spectra, and database search identified these compounds as cytochalasins. Systematic dereplication helped identify a peak at m/z 540.26 [M + H]⁺ as the new compound. Further, the identified compound was purified by high-performance liquid chromatography and characterized by 2D NMR to be 19,20-epoxycytochalasin N1, a new optical isomer of 19,20-epoxycytochalasin-N. It exhibited substantial cytotoxicity with IC₅₀ values ranging from 1.34 to 19.02 μM. This study shows a fast approach for dereplicating and identifying novel cytochalasin metabolites in crude extracts.

Microbial cultures, especially bacteria, fungi, and yeasts, have been earlier recognized as laboratory hazards dealing with various infectious agents. Microbiological laboratories are often unique, exceptional, and their working environment poses special contagious disease risks to individual workers who are in constant contact with or near them. So far, various reports are available regarding associated laboratory cases of typhoid, glanders, brucellosis, cholera, polio, tetanus, and other such diseases. A published survey of voluntary responses from 88 facilities that were associated with laboratory infection concluded that Shigella was the most common infecting agent, followed by Brucella, Salmonella, and Staphylococcus aureus. Neisseria meningitidis was also perceived as a commonly acquired infection, and therefore the handling of microbial cultures or specimens or the inhalation of dust in the microbial system is strikingly dangerous to laboratory workers. Realizing the need for tackling these hazards, specific biosafety guidelines had been developed nationally and internationally to protect laboratory 148researchers in microbiological laboratories through a medley of biosecurity safeguards. They also include procedures for risk assessment and management techniques besides adopting appropriate laboratory experimental practices. The details of such systems and guidelines shall be elucidated herewith.

Targeting the main three networking systems viz. Las, RhI and PQS via natural quenchers is a new ray of hope for combating the persistent behavior of Pseudomonas aeruginosa. In the bacterial chemical vocabulary pyocyanin, N-AHLs and rhamnolipids are the main keywords, which are responsible for the social and nomadic behavior of P. aeruginosa. In the present work LCMS-based real-time qualitative and quantitative analysis of pyocyanin, green phenazine, N-AHLs, and rhamnolipids were performed. The quantitative analysis indicates that the production of pyocyanin and NHSLs increases with time while the production of rhamnolipids discontinued after 16 Hrs. This indicates the emergence of persisters in the medium instead of planktonic cells. Rhamnolipids being acts as a surfactant enhances the motility of the bacterial cells whereas, the pyocyanin is responsible for the biofilm formation. In microtiter plate based assay an effect of capsaicin and 6-gingerol was recorded. In the presence of capsaicin and 6-gingerol, substantial fall in the production of rhamnolipids, phenazine, quinolone, and N-AHLs was observed. Most interestingly, the 6-gingerol treatment led to the drastic decrease of rhamnolipids, phenazine, quinolone and N-AHLs than capsaicin. These studies demonstrate the effectiveness of the capsaicin and 6-gingerol on Las, PQS and Rhl circuits in a bacterium in order to understand the persistent and social behavior. Here we are reporting LC-MS based qualitative and quantitative analysis of QS molecules by taking a low volume of culture (up to 200 μl). This method can be used as a platform to screen the new antivirulence agents for fighting the resistant behavior of P. aeruginosa during biofilm formation.