Identification of Lipstatin-Producing Ability in Streptomyces virginiae CBS 314.55 Using Dereplication Approach

Streptomicete su poznate kao bogat izvor bioaktivnih metabolita, poput sekundarnog metabolita lipstatina, koji ima vrlo karakterističnu strukturu β-laktona, a upotrebljava se kao intermedijar u proizvodnji lijeka za mršavljenje, komercijalnog naziva orlistat. Dublje razumijevanje distribucije identičnih ili strukturno sličnih spojeva, izoliranih iz taksonomski sličnih skupina mikroorganizama, bitno je za otkrivanje novih biološki aktivnih spojeva ili kvalitetnijih sojeva što proizvode poznate metabolite od velikog značaja za medicinu. Samo su dva soja, neovisni izolati vrste S. toxytricini, poznati kao proizvođači lipstatina. Prema današnjim taksonomskim spoznajama, vrsta S. toxytricini pripada fenotipskoj skupini S. lavendulae. Taksonomskom dereplikacijom i ispitivanjem in vitro inhibicije lipaze pomoću p-nitrofenolnih derivata C4 i C16 masnih kiselina istraženi su odabrani sojevi fenotipske skupine S. lavendulae iz javno dostupnih kolekcija mikroorganizama. Utvrđeno je da bakterijska kultura soja Streptomyces virginiae CBS 314.55 izrazito inhibira lipazu. Pomoću metoda HPLC i LC-MS/MS po prvi je put otkriveno da ovaj novi soj proizvodi metabolit strukture identične lipstatinu. Dokazano je da se novi soj S. virginiae morfološki i fiziološki bitno razlikuje od sojeva S. toxytricini, ali da im je proizvodni potencijal sličan. Time je potvrđena mogućnost učinkovite primjene metode dereplikacije za brzu identifikaciju novih industrijskih sojeva iz javno dostupnih kolekcija mikroorganizama.Streptomyces species are prolific producers of bioactive metabolites, such as β-lactone-containing lipstatin produced by Streptomyces toxytricini, an intermediate used in semi-synthetic process for production of anti-obesity drug orlistat. Understanding the distribution of identical or structurally similar molecules produced by a taxonomic group is of particular importance when trying to isolate novel biologically active compounds or strains producing known metabolites of medical importance with potentially improved properties. Until now, only two independent isolates of S. toxytricini species have been known to be producers of lipstatin. According to the current taxonomic criteria, S. toxytricini belongs to Streptomyces lavendulae phenotypic cluster. Taxonomy-based dereplication approach coupled with in vitro assay was applied to screen the S. lavendulae phenotypic cluster for production of lipstatin-like lipase inhibitors using synthetic p-nitrophenol derivatives of C4 and C16 lipids. Screening the available strains from public collections belonging to S. lavendulae phenotypic cluster, high lipase inhibitory activity was identified in the Streptomyces virginiae CBS 314.55 culture supernatants. HPLC and LC-MS/MS confirmed lipstatin production by a new Streptomyces species for the first time. We have demonstrated that the new lipstatin-producing strain S. virginiae morphologically and physiologically differs from S. toxytricini substantially; however, the production capacity of the newly identified lipstatin-producing species S. virginiae is comparable to S. toxytricini. We have thus demonstrated the effectiveness of a simple and affordable dereplication approach for identification of potentially novel and useful industrial strains available in public culture collections

The public forestry service role in controlling Goriški Kras fire and consequences of the fire for forest ecosystems

Požar Goriški Kras, ki je vzplamtel 15. 7. 2022, pogašen pa je bil 29. 7. 2022, je doslej največji požar v Sloveniji, saj je zajel skupaj 3.707 ha površin, od tega 2.902 ha gozdov. Pogorela površina v Sloveniji in Italiji skupaj obsega okoli 4.500 ha. V intervencijo gašenja požara je bila že prvi dan nastanka požara vključena javna gozdarska služba, ki jo opravlja Zavod za gozdove Slovenije. Gozdarji so štabu za vodenje intervencije dali na voljo gozdarske karte z zarisom vseh prometnic. Zaradi dobrega poznavanja terena je bila glavna naloga ZGS sprva pomagati posameznim gasilnim enotam pri orientaciji v prostoru in usmerjanju po protipožarnih presekah in gozdnih cestah. V času največjega razvoja požara so bile naloge delavcev ZGS preusmerjene v sečnjo ob prometnicah in naseljih, kjer bi bilo mogoče ustaviti širjenje požara. V aktivnost so se vključili tudi gozdarji družbe Slovenski državni gozdovi (SiDG) in iz ZGS vpoklicani izvajalci sečnje in drugih del na protipožarnih presekah ter prostovoljci. Neposredna škoda v gozdovih je bila ocenjena na 24,9 milijona evrov, požar pa je pomembno prizadel tudi ekološke in socialne funkcije gozdaThe Goriški Kras fire which flared up on July 15, 2022, and was extinguished on July 29, 2022, represents the largest fire in Slovenia up to now since it engulfed a total of 3.707 ha of the areas, thereof 2.902 ha of forests. The whole burntarea in Slovenia and Italy covers about 4.500 ha. The public forestry service performed by the Slovenia Forest Service (SFS) was incorporated into the intervention on the first day of the fire. The foresters placed forestry maps with the delineation of all forest roads at the Intervention headquarters’ disposal. Due to their thorough terrain knowledge, at first, the main ZGS task was to help individual fire-fighting units with their spatial orientation and direct them on the firebreaks and forest roads. In the time of the maximum fire development, the SFS workers’ tasks were redirected into the execution of felling along the traffic roads and settlements where it could have been possible to stop the fire from spreading. The foresters of the Slovenian State Forests (SiDG) company and other forestry companies and works, called up by the SFS, and volunteers were incorporated into the activities. The direct damage in the forests has been estimated to 24.9 million EUR. Furthermore, the fire also significantly affected the ecological and social functions of the forest