Zur Entstehung einer Imbalance im limbo-präfrontalen System bei Meriones unguiculatus : der Einfluss restriktiver Isolationsaufzucht und einer postnatalen Methamphetamin-Intoxikation auf die monoaminergen Transmitter Dopamin und Serotonin

Busche A. Zur Entstehung einer Imbalance im limbo-präfrontalen System bei Meriones unguiculatus : der Einfluss restriktiver Isolationsaufzucht und einer postnatalen Methamphetamin-Intoxikation auf die monoaminergen Transmitter Dopamin und Serotonin. Bielefeld (Germany): Bielefeld University; 2004.Schädigende Umwelteinflüsse können zu massiven Störungen der Hirnreifung führen. Störungen im limbo-präfrontalen System, welches als das höchste assoziative System des Gehirns gilt, werden mit verschiedenen psychischen Erkrankungen in Verbindung gebracht. An unserem Tiermodell (Meriones unguiculatus) konnte durch frühere Arbeiten gezeigt werden, dass sowohl eine chronische Schädigung in Form der restriktiven Isolationsaufzucht als auch eine akute Schädigung in Form der einmaligen Methamphetamin-Intoxikation am postnatalen Tag 14 Einfluss nehmen auf die Reifung der Monoamine Dopamin (DA) und Serotonin (5HT) im präfrontalen Kortex und Nucleus accumbens. Ziel dieser Arbeit war es, den Einfluss dieser beiden experimentellen Parameter auf die postnatale DA und 5HT Reifung in der Formatio hippocampalis zu untersuchen und darüber hinaus ein Gesamtbild der Veränderungen dieser Monoamine innerhalb des limbo-präfrontalen Systems zu erstellen. Insgesamt zeigt sich, dass beide Transmitter, DA und 5HT, in allen untersuchten Arealen des limbo-präfrontalen Systems in ihrer postnatalen Reifung stark beeinflusst werden. Insbesondere die strukturellen Veränderungen der DAergen Projektionen im limbo-präfrontalen System weisen auf eine, sich im Laufe des Reifungsprozesses entwickelnden, Imbalance innerhalb dieses Systems hin, die in Form einer Hypoinnervation des präfrontalen Kortex und einer Hyperinnervation des entorhinalen Kortex und der Amygdala auftritt. Lokale Veränderungen der monoaminergen Innervation können sowohl die Aktivitäten innerhalb der einzelnen Regionen als auch die Konnektivität zwischen den einzelnen Arealen beeinträchtigen und somit die Funktion des Gesamtsystems erheblich stören. Unsere Befunde unterstützen aktuelle Modellvorstellungen zur Schizophrenie, die eine Hypoaktivierung des präfrontalen Kortex und eine Hyperaktivierung limbischer Areale postulieren

Generation and characterisation of an Arabidopsis thaliana f3h/fls1/ans triple mutant that accumulates eriodictyol derivatives

Schilbert H, Busche M, Sáez V, et al. Generation and characterisation of an Arabidopsis thaliana f3h/fls1/ans triple mutant that accumulates eriodictyol derivatives. BMC Plant Biology. 2024;24(1): 99.**Background** Flavonoids are plant specialised metabolites, which derive from phenylalanine and acetate metabolism. They possess a variety of beneficial characteristics for plants and humans. Several modification steps in the synthesis of tricyclic flavonoids cause for the amazing diversity of flavonoids in plants. The 2-oxoglutarate-dependent dioxygenases (2-ODDs) flavanone 3-hydroxylase (F3H, synonym FHT), flavonol synthase (FLS) and anthocyanidin synthase (ANS, synonym leucoanthocyanidin dioxygenase (LDOX)), catalyse oxidative modifications to the central C ring. They are highly similar and have been shown to catalyse, at least in part, each other’s reactions. FLS and ANS have been identified as bifunctional enzymes in many species, includingArabidopsis thaliana, stressing the capability of plants to bypass missing or mutated reaction steps on the way to flavonoid production. However, little is known about such bypass reactions and the flavonoid composition of plants lacking all three central flavonoid 2-ODDs. **Results** To address this issue, we generated af3h/fls1/ansmutant, as well as the corresponding double mutants and investigated the flavonoid composition of this mutant collection. Thef3h/fls1/ansmutant was further characterised at the genomic level by analysis of a nanopore DNA sequencing generated genome sequence assembly and at the transcriptomic level by RNA-Seq analysis. The mutant collection established, including the novel double mutantsf3h/fls1andf3h/ans, was used to validate and analyse the multifunctionalities of F3H, FLS1, and ANSin planta. Metabolite analyses revealed the accumulation of eriodictyol and additional glycosylated derivatives in mutants carrying thef3hmutant allele, resulting from the conversion of naringenin to eriodictyol by flavonoid 3’-hydroxylase (F3’H) activity. **Conclusions** We describe thein plantamultifunctionality of the three central flavonoid 2-ODDs fromA. thalianaand identify a bypass in thef3h/fls1/anstriple mutant that leads to the formation of eriodictyol derivatives. As (homo-)eriodictyols are known as bitter taste maskers, the annotated eriodictyol (derivatives) and in particular the observations made on theirin plantaproduction, could provide valuable insights for the creation of novel food supplements

Generation and characterisation of an Arabidopsis thaliana f3h/fls1/ans triple mutant that accumulates eriodictyol derivatives

Abstract Background Flavonoids are plant specialised metabolites, which derive from phenylalanine and acetate metabolism. They possess a variety of beneficial characteristics for plants and humans. Several modification steps in the synthesis of tricyclic flavonoids cause for the amazing diversity of flavonoids in plants. The 2-oxoglutarate-dependent dioxygenases (2-ODDs) flavanone 3-hydroxylase (F3H, synonym FHT), flavonol synthase (FLS) and anthocyanidin synthase (ANS, synonym leucoanthocyanidin dioxygenase (LDOX)), catalyse oxidative modifications to the central C ring. They are highly similar and have been shown to catalyse, at least in part, each other’s reactions. FLS and ANS have been identified as bifunctional enzymes in many species, including Arabidopsis thaliana, stressing the capability of plants to bypass missing or mutated reaction steps on the way to flavonoid production. However, little is known about such bypass reactions and the flavonoid composition of plants lacking all three central flavonoid 2-ODDs. Results To address this issue, we generated a f3h/fls1/ans mutant, as well as the corresponding double mutants and investigated the flavonoid composition of this mutant collection. The f3h/fls1/ans mutant was further characterised at the genomic level by analysis of a nanopore DNA sequencing generated genome sequence assembly and at the transcriptomic level by RNA-Seq analysis. The mutant collection established, including the novel double mutants f3h/fls1 and f3h/ans, was used to validate and analyse the multifunctionalities of F3H, FLS1, and ANS in planta. Metabolite analyses revealed the accumulation of eriodictyol and additional glycosylated derivatives in mutants carrying the f3h mutant allele, resulting from the conversion of naringenin to eriodictyol by flavonoid 3’-hydroxylase (F3’H) activity. Conclusions We describe the in planta multifunctionality of the three central flavonoid 2-ODDs from A. thaliana and identify a bypass in the f3h/fls1/ans triple mutant that leads to the formation of eriodictyol derivatives. As (homo-)eriodictyols are known as bitter taste maskers, the annotated eriodictyol (derivatives) and in particular the observations made on their in planta production, could provide valuable insights for the creation of novel food supplements

Administration of oral methylphenidate during adolescence prevents suppressive development of dopamine projections into prefrontal cortex and amygdala after an early pharmacological challenge in gerbils

Grund T, Teuchert-Noodt G, Busche A, et al. Administration of oral methylphenidate during adolescence prevents suppressive development of dopamine projections into prefrontal cortex and amygdala after an early pharmacological challenge in gerbils. BRAIN RESEARCH. 2007;1176:124-132.The enduring effects of postweaning subchronic methylphenidate (MP) treatment and/or previous early preweaning methamphetamine (MA) application on dopamine (DA) fiber density were investigated in multiple cortical and subcortical areas of the gerbil brain. The study aimed to explore three questions: (1) is the development of DA fiber innervation in control animals sensitive to a clinically relevant subchronic treatment with MP? (2) Is the development of DA fiber innervation in the forebrain altered by a single early MA challenge? (3) if so, might the subsequent institution of a therapeutically relevant MP application scheme interfere with such early induced alternative developmental trajectories for DA fiber innervation? For this purpose, gerbils pretreated both with saline and MA (50 mg/kg, i. p.) on day 14 received either H2O or MP (5 mg/kg) orally on days 30 to 60. On day 90, DA fibers were immunohistochemically detected and quantified. As a result, MP on its own did not have any significant influence on the postnatal development of the DA fiber systems, whereas it prevented a previously MA triggered suppressive development of DA fiber innervation in the prefrontal cortex and amygdala complex (30% less fiber innervation in both areas). Thus, MP prevented previously initiated miswiring of DA fibers from actually being implemented in the gerbil forebrain. During earlier studies, rather complex miswiring has been documented in response to an early preweaning MA challenge. This miswiring was associated with functional deficits resembling some of the symptoms of patients with ADHD. Therefore, morphogenetic properties of MP need further attention. (C) 2007 Elsevier B.V. All rights reserved

Transcriptomic analysis of the dual response of Rhodococcus aetherivorans BCP1 to inorganic arsenic oxyanions

Bacterial strains belonging to the genus Rhodococcus are capable to degrade various toxic organic compounds and tolerate high concentrations of metal(loid)s. We have previously shown that R. aetherivorans BCP1 is resistant to various levels of the two arsenic inorganic species, arsenite [As(III)] and arsenate [As(V)]. However, while arsenite showed toxic effects as early as 5 mM, arsenate at 30 mM even boosted the growth rate of BCP1 cells and was only toxic at concentrations > 100 mM. Since such behavior could be linked to peculiar aspects of its metabolism, the transcriptomic analysis of BCP1 cells exposed to 5 mM As(III) and 30 mM As(V), was performed in this work. The aim was to clarify the mechanisms underlying the arsenic stress response of the two growth phenotypes in the presence of the two different oxyanions. The results revealed that As(III) induced higher activity of ROS-scavenging enzymes as compared to As(V) in relation with the expression of enzymes involved in cellular damage recovery and redox buffers/cofactors (ergothioneine, mycofactocin and mycothiol). Further, As(III) downregulated pathways related to cell division while both oxyanions downregulated genes involved in glycolysis. Notably, As(V) induced the expression of enzymes participating in the synthesis of metallophores and rearranged the central and energetic metabolism, also inducing alternative pathways for ATP synthesis and glucose consumption. This study, in providing the transcriptomic data on R. aetherivorans exposed to arsenic oxyanions, sheds some light on the plasticity of rhodococcal response to arsenic stress, which may be important for the improvement of biotechnological applications

Lacticaseibacillus parahuelsenbergensis sp. nov., Lacticaseibacillus styriensis sp. nov. and Lacticaseibacillus zeae subsp. silagei subsp. nov., isolated from different grass and corn silage

Grabner F. M, Grabner H. M, Schein H, et al. Lacticaseibacillus parahuelsenbergensis sp. nov., Lacticaseibacillus styriensis sp. nov. and Lacticaseibacillus zeae subsp. silagei subsp. nov., isolated from different grass and corn silage. International Journal of Systematic and Evolutionary Microbiology. 2024;74(7).Four rod-shaped, non-motile, non-spore-forming, facultative anaerobic, Gram-stain-positive lactic acid bacteria, designated as EB0058T, SCR0080, LD0937Tand SCR0063T, were isolated from different corn and grass silage samples. The isolated strains were characterized using a polyphasic approach and EB0058Tand SCR0080 were identified asLacticaseibacillus zeaeby 16S rRNA gene sequence analysis. Based on whole-genome sequence-based characterization, EB0058Tand SCR0080 were separated into a distinct clade fromLacticaseibacillus zeaeDSM 20178T, together with CECT9104 and UD2202, whose genomic sequences are available from NCBI GenBank. The average nucleotide identity (ANI) values within the new subgroup are 99.9 % and the digital DNA–DNA hybridization (dDDH) values are 99.3–99.9 %, respectively. In contrast, comparison of the new subgroup with publicly available genomic sequences ofL. zeaestrains, including the type strain DSM 20178T, revealed dDDH values of 70.2–72.5 % and ANI values of 96.2–96.6 %. Based on their chemotaxonomic, phenotypic and phylogenetic characteristics, EB0058Tand SCR0080 represent a new subspecies ofL. zeae. The nameLacticaseibacillus zeaesubsp.silageisubsp. nov. is proposed with the type strain EB0058T(=DSM 116376T=NCIMB 15474T). According to the results of 16S rRNA gene sequencing, LD0937Tand SCR0063Tare members of theLacticaseibacillusgroup. The dDDH value between the isolates LD0937Tand SCR0063Twas 67.6 %, which is below the species threshold of 70 %, clearly showing that these two isolates belong to different species. For both strains, whole genome-sequencing revealed that the closest relatives within theLacticaseibacillusgroup wereLacticaseibacillus huelsenbergensisDSM 115425(dDDH 66.5 and 65.9 %) andLacticaseibacillus caseiDSM 20011T(dDDH 64.1 and 64.9 %). Based on the genomic, chemotaxonomic and morphological data obtained in this study, two novel species,Lacticaseibacillus parahuelsenbergensissp. nov. andLacticaseibacillus styriensissp. nov. are proposed and the type strains are LD0937T(=DSM 116105T=NCIMB 15471T) and SCR0063T(=DSM 116297T=NCIMB 15473T), respectively

Additional file 1 of Generation and characterisation of an Arabidopsis thaliana f3h/fls1/ans triple mutant that accumulates eriodictyol derivatives

Supplementary Material

Exploring engineered vesiculation by Pseudomonas putida KT2440 for natural product biosynthesis

Bitzenhofer NL, Höfel C, Thies S, et al. Exploring engineered vesiculation by Pseudomonas putida KT2440 for natural product biosynthesis. Microbial Biotechnology. 2023.Pseudomonas species have become promising cell factories for the production of natural products due to their inherent robustness. Although these bacteria have naturally evolved strategies to cope with different kinds of stress, many biotechnological applications benefit from engineering of optimised chassis strains with specially adapted tolerance traits. Here, we explored the formation of outer membrane vesicles (OMV) of Pseudomonas putida KT2440. We found OMV production to correlate with the recombinant production of a natural compound with versatile beneficial properties, the tripyrrole prodigiosin. Further, several P.putida genes were identified, whose up- or down-regulated expression allowed controlling OMV formation. Finally, genetically triggering vesiculation in production strains of the different alkaloids prodigiosin, violacein, and phenazine-1-carboxylic acid, as well as the carotenoid zeaxanthin, resulted in up to three-fold increased product yields. Consequently, our findings suggest that the construction of robust strains by genetic manipulation of OMV formation might be developed into a useful tool which may contribute to improving limited biotechnological applications. © 2023 The Authors. Microbial Biotechnology published by Applied Microbiology International and John Wiley & Sons Ltd