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Compositional analysis is an important component of an integrated comparative approach to assessing the food and feed safety of new crops developed using biotechnology. As part of the safety assessment of cassava brown streak disease resistant 4046 cassava, a comprehensive assessment of proximates, minerals, amino acids, fatty acids, vitamins, anti-nutrients, and secondary metabolites was performed on leaf and storage root samples of 4046 cassava and its non-transgenic parental control, TME 204, collected from confined field trials in Kenya and Uganda over two successive cropping cycles. Among the 100 compositional components that were assessed in samples of 4046 and control TME 204 cassava roots (47 components) and leaves (53 components), there were no nutritionally relevant differences noted. Although there were statistically significant differences between the transgenic and control samples for some parameters, in most cases the magnitudes of these differences were small ( < 20%), and in every case where comparative literature data were available, the mean values for 4046 and control cassava samples were within the range of normal variation reported for the compositional component in question. Overall, no consistent patterns emerged to suggest that biologically meaningful adverse changes in the composition or nutritive value of the leaves or storage roots occurred as an unintended or unexpected consequence of the genetic modification resulting in 4046 cassava. The data presented here provide convincing evidence of the safety of 4046 cassava with respect to its biochemical composition for food and feed, and it could be considered as safe as its non-transgenic control. [ABSTRACT FROM AUTHOR]

Bacillus genus comprises an important number of species which produce a wide range of secondary metabolites displaying a broad spectrum of activity and great structural diversity. The genome sequences of an important number of species have been published and a large number of orphan genes reported. This review, covering all the literature in this field up to end of 2011, summarizes and compares the genetic potential of these organisms from the point of view of bioactive nonribosomal peptide production and their application as antibiotics, plant pathogen biocontrol, promotion of plant growth, etc. The biological and structural studies of the peptides isolated from Bacillus species are revised and some aspects of the biosynthesis of these metabolites and related compounds are discussed. [ABSTRACT FROM AUTHOR]

Thiochroman derivatives are highly versatile molecules widely used for the synthesis of novel heterocycles and bioactive compounds. In our study, we conducted the biotransformation of thiochroman-4-ol ( 1 ) and 6-chlorothiochroman-4-ol ( 1a ) using the marine-derived fungal strains Emericellopsis maritima BC17 and Purpureocillium lilacinum BC17-2. Biotransformations yielded ten known thiochroman derivatives along with the compound 1-(5-chloro-2-(methylthio)phenyl)propane-1,3-diol ( 6a ), which was described for the first time. Moreover, we successfully characterized the stereoisomers of sulfoxides 3 and 3a . Their structures and absolute configurations were established though comprehensive analyses of NMR, HR ESI-MS, and ECD spectra, as well as by using Mosher's method. Antimicrobial activity of the isolated metabolites was evaluated against bacterial and fungal human pathogens, specifically Staphylococcus aureus ATCC 29213, Escherichia coli ATCC25922, and Candida albicans HPM-1922816.

Botrytis cinerea is a necrotrophic fungus that causes considerable economic losses in commercial crops. Fungi of the genus Botrytis exhibit great morphological and genetic variability, ranging from non-sporogenic and non-infective isolates to highly virulent sporogenic ones. There is growing interest in the different isolates in terms of their methodological applications aimed at gaining a deeper understanding of the biology of these fungal species for more efficient control of the infections they cause. This article describes an improvement in the protoplast production protocol from non-sporogenic isolates, resulting in viable protoplasts with regenerating capacity. The method improvements consist of a two-day incubation period with mycelium plugs and orbital shaking. Special mention is made of our preference for the VinoTaste Pro enzyme in the KC buffer as a replacement for Glucanex, as it enhances the efficacy of protoplast isolation in B459 and B371 isolates. The methodology described here has proven to be very useful for biotechnological applications such as genetic transformations mediated by the CRISPR/Cas9 tool.

The genome sequencing of Botrytis cinerea supplies a general overview of the map of genes involved in secondary metabolite synthesis. B. cinerea genomic data reveals that this phytopathogenic fungus has seven sesquiterpene cyclase ( Bcstc ) genes that encode proteins involved in the farnesyl diphosphate cyclization. Three sesquiterpene cyclases (BcStc1, BcStc5 and BcStc7) are characterized, related to the biosynthesis of botrydial, abscisic acid and (+)-4-epi-eremophilenol, respectively. However, the role of the other four sesquiterpene cyclases (BcStc2, BcStc3, BcStc4 and BcStc6) remains unknown. BcStc3 is a well-conserved protein with homologues in many fungal species, and here, we undertake its functional characterization in the lifecycle of the fungus. A null mutant Δ Bcstc3 and an overexpressed- Bcstc3 transformant (Ov Bcstc3 ) are generated, and both strains show the deregulation of those other sesquiterpene cyclase-encoding genes ( Bcstc1 , Bcstc5 and Bcstc7 ). These results suggest a co-regulation of the expression of the sesquiterpene cyclase gene family in B. cinerea . The phenotypic characterization of both transformants reveals that BcStc3 is involved in oxidative stress tolerance, the production of reactive oxygen species and virulence. The metabolomic analysis allows the isolation of characteristic polyketides and eremophilenols from the secondary metabolism of B. cinerea , although no sesquiterpenes different from those already described are identified.

Glucosinolates, the main secondary metabolites accumulated in cruciferous flora, have a major impact on fortifying plant immunity against diverse pathogens. Although Botrytis cinerea exhibits varying sensitivity to these compounds, current research has yet to fully understand the intricate mechanisms governing its response to glucosinolates. Different species of the genus Botrytis were exposed to glucosinolate-derived isothiocyanates, revealing that B. fabae , B. deweyae , and B. convolute , species with the mfsG transporter gene (Bcin06g00026) not detected with PCR, were more sensitive to isothiocyanates than Botrytis species containing that gene, such as B. cinerea , B. pseudocinerea , and B. byssoidea . This finding was further corroborated by the inability of species with the mfsG gene not detected with PCR to infect plants with a high concentration of glucosinolate-derived isothiocyanates. These results challenge established correlations, revealing varying aggressiveness on different plant substrates. An expression analysis highlighted the gene's induction in the presence of isothiocyanate, and a bioinformatic investigation identified homologous genes in other Botrytis species. Our study underscored the importance of advanced biotechnology to help understand these proteins and thus offer innovative solutions for agriculture.

The fungal strain BC17 was isolated from sediments collected in the intertidal zone of the inner Bay of Cadiz and characterized as Emericellopsis maritima . On the basis of the one strain-many compounds (OSMAC) approach, four new eremophilane-type sesquiterpenes ( 1 - 4 ), together with thirteen known derivatives ( 5 - 17 ) and two reported diketopiperazines ( 18 , 19 ), were isolated from this strain. The chemical structures and absolute configurations of the new compounds were determined through extensive NMR and HRESIMS spectroscopic studies and ECD calculation. Thirteen of the isolated eremophilanes were examined for cytotoxic and antimicrobial activities. PR toxin ( 16 ) exhibited cytotoxic activity against HepG2, MCF-7, A549, A2058, and Mia PaCa-2 human cancer cell lines with IC 50 values ranging from 3.75 to 33.44 µM. (+)-Aristolochene ( 10 ) exhibited selective activity against the fungal strains Aspergillus fumigatus ATCC46645 and Candida albicans ATCC64124 at 471 µM.

Marine microorganisms account for over 90% of ocean biomass and their diversity is believed to be the result of their ability to adapt to extreme conditions of the marine environment. Biotransformations are used to produce a wide range of high-added value materials, and marine-derived fungi have proven to be a source of new enzymes, even for activities not previously discovered. This review focuses on biotransformations by fungi from marine environments, including bioremediation, from the standpoint of the chemical structure of the substrate, and covers up to September 2022., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Virués-Segovia, Muñoz-Mira, Durán-Patrón and Aleu.)

The ascomycete Botrytis cinerea Pers. Fr., classified within the family Sclerotiniaceae, is the agent that causes grey mould disease which infects at least 1400 plant species, including crops of economic importance such as grapes and strawberries. The life cycle of B. cinerea consists of two phases: asexual (anamorph, Botrytis cinerea Pers. Fr.) and sexual (teleomorph, Botryotinia fuckeliana (de Bary) Wetzel). During the XVI International Symposium dedicated to the Botrytis fungus, which was held in Bari in June 2013, the scientific community unanimously decided to assign the most widely used name of the asexual form, Botrytis , to this genus of fungi. However, in the literature, we continue to find articles referring to both morphic stages. In this review, we take stock of the genes and metabolites reported for both morphic forms of B. cinerea between January 2015 and October 2022.

The compounds 11,12,13-tri- nor -sesquiterpenes are degraded sesquiterpenoids which have lost the C 3 unit of isopropyl or isopropenyl at C-7 of the sesquiterpene skeleton. The irregular C-backbone originates from the oxidative removal of a C 3 side chain from the C 15 sesquiterpene, which arises from farnesyl diphosphate (FDP). The C 12 -framework is generated, generally, in all families of sesquiterpenes by oxidative cleavage of the C 3 substituent, with the simultaneous introduction of a double bond. This article reviews the isolation, biosynthesis and biological activity of this special class of sesquiterpenes, the 11,12,13-tri- nor- sesquiterpenes.

Marine microorganisms have proven to be a source of new natural products with a wide spectrum of biological activities relevant in different industrial sectors. The ever-increasing number of sequenced microbial genomes has highlighted a discrepancy between the number of gene clusters potentially encoding the production of natural products and the actual number of chemically characterized metabolites for a given microorganism. Homologous and heterologous expression of these biosynthetic genes, which are often silent under experimental laboratory culture conditions, may lead to the discovery of new cryptic natural products of medical and biotechnological interest. Several new genetic and cultivation-based strategies have been developed to meet this challenge. The OSMAC approach (one strain-many compounds), based on modification of growth conditions, has proven to be a powerful strategy for the discovery of new cryptic natural products. As a direct extension of this approach, the addition of chemical elicitors or epigenetic modifiers have also been used to activate silent genes. This review looks at the structures and biological activities of new cryptic metabolites from marine-derived microorganisms obtained using the OSMAC approach, the addition of chemical elicitors, and enzymatic inhibitors and epigenetic modifiers. It covers works published up to June 2021.

Botrytis cinerea has high potential for the production of specialized metabolites. The recent resequencing of the genome of the B05.10 strain using PacBio technology and the resulting update of the Ensembl Fungi (2017) database in the genome sequence have been instrumental in identifying new genes that could be involved in secondary metabolism. Thus, a new sesquiterpene cyclase (STC) coding gene (Bcstc7) has been included in the gene list from this phytopathogenic fungus. We recently constructed the null and complement transformants in STC7 which enabled us to functionally characterize this STC. Deletion of the Bcstc7 gene abolished (+)-4-epi-eremophilenol biosynthesis, and could then be re-established by complementing the null mutant with the Bcstc7 gene. Chemical analysis of the complemented transformant suggests that STC7 is the principal enzyme responsible for the key cyclization step of farnesyl diphosphate (FDP) to (+)-4-epi-eremophil-9-en-11-ols. A thorough analysis of the metabolites produced by two wild-type strains, B05.10 and UCA992, and the complemented mutant compl ΔBcstc7 niaD , revealed the isolation and structural characterization of six 11,12,13-tri-nor-eremophilene derivatives, in addition to a large number of known eremophilen-11-ol derivatives. The structural characterization was carried out by extensive spectroscopic techniques. The biosynthesis of these compounds is explained by a retroaldol reaction or by dehydration and oxidative cleavage of C11-C13 carbons. This is the first time that this interesting family of degraded eremophilenols has been isolated from the phytopathogenous fungus B. cinerea., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)