On the steric course of the microbial generation of (Z6)-gamma-dodecenolactone from (10R,S) 10-hydroxy-octadeca-(E8, Z12)-dienoic acid

Summary (Z6)-gamma-dodecenolactone samples produced endogenously inFusarium poae and biogenerated from (10R, S) 10-hydroxy-octadeca-(E8, Z12)-dienoic acid inCladosporium suaveolens show (R) and (S) configurations, respectively.     

Synthesis and biological evaluation of novel heteroring-annulated pyrrolino-tetrahydroberberine analogues as antioxidant agents

Tetrahydroberberine (THB), otherwise known as canadine, is a natural alkaloid showing significant pharmacological properties and antioxidant protection against oxidative damage. Herein, we synthetized structurally complex THB analogues, namely pyrrolino-tetrahydroberberines (PTHBs) 4a–g, containing the pyrrolino[2,3-b]pyridine system, by means of the reactions of 1,2-diaza-1,3-dienes and 7,8-dihydroberberine. Aim of the study was to explore the in vitro antioxidant properties of PTHBs in comparison to THB thus to identify the most effective against free radical-induced oxidative injury, by using three different antioxidant tests: the ORAC method, the DNA nicking assay, and the DCFH-DA cellular assay. As a result, PTHB 4d emerged among the other THB analogues by exhibiting the best antioxidant properties. First, it was the only compound having an ORAC value completely comparable to that of THB, indicating the same ability to neutralize peroxyl radicals. Secondly, 4d showed an even better antioxidant capacity than THB in protecting DNA against ferrous ion-induced strand breaks. These observations were also confirmed in NCTC-2544 human keratinocytes exposed to hydrogen peroxide. Indeed, 4d protected cells against oxidation more efficiently than THB both in the short (1 and 3?h) and long (24?h) period of incubation, possibly suggesting increased cell membrane permeability and/or intracellular stability of 4d as compared to THB.     

Simplified lipid II-binding antimicrobial peptides: Design,synthesis and antimicrobial activity of bioconjugates of nisin rings A and B with pore-forming peptides

New designs of antimicrobial peptides are urgently needed in order to combat the threat posed by the recent increase of resistance to antibiotics. In this paper, we present a new series of antimicrobial peptides, based on the key structural features of the lantibiotic nisin. We have simplified the structure of nisin by conjugating the lipid II-binding motif at the N-terminus of nisin to a series of cationic peptides and peptoids with known antibacterial action and pore-forming properties. Hybrid peptides, where a hydrophilic PEG4 linker was used, showed good antibacterial activity against Micrococcus luteus.     

Zc3h10 is a novel mitochondrial regulator

Mitochondria are the energy‐generating hubs of the cell. In spite of considerable advances, our understanding of the factors that regulate the molecular circuits that govern mitochondrial function remains incomplete. Using a genome‐wide functional screen, we identify the poorly characterized protein Zinc finger CCCH‐type containing 10 (Zc3h10) as regulator of mitochondrial physiology. We show that Zc3h10 is upregulated during physiological mitochondriogenesis as it occurs during the differentiation of myoblasts into myotubes. Zc3h10 overexpression boosts mitochondrial function and promotes myoblast differentiation, while the depletion of Zc3h10 results in impaired myoblast differentiation, mitochondrial dysfunction, reduced expression of electron transport chain (ETC) subunits, and blunted TCA cycle flux. Notably, we have identified a loss‐of‐function mutation of Zc3h10 in humans (Tyr105 to Cys105) that is associated with increased body mass index, fat mass, fasting glucose, and triglycerides. Isolated peripheral blood mononuclear cells from individuals homozygotic for Cys105 display reduced oxygen consumption rate, diminished expression of some ETC subunits, and decreased levels of some TCA cycle metabolites, which all together derive in mitochondrial dysfunction. Taken together, our study identifies Zc3h10 as a novel mitochondrial regulator.     

InDel markers for monitoring the introgression of downy mildew resistance from wild relatives into grape varieties

We identified haplotype-tagging insertion/deletions (InDels) for downy mildew resistance (Rpv3-1) in grapevine and converted them into InDel markers. InDel-25,941 and InDel-26,032 were validated by fragment analysis via capillary electrophoresis in 174 varieties of Vitis vinifera, 50 resistant varieties of the ‘Seibel 4614’ lineage that share Rpv3-1 by descent, and in 83 Vitis accessions. Amplicon sequencing of ancestral and derived alleles revealed that both mutations were caused by deletions. The 25,941-deletion is most likely recent. The derived allele is present only in resistant varieties obtained from ‘Seibel 4614’ and has originated in North American populations through two successive deletions within a predicted multiple stem-loop ssDNA structure, consisting of three nearby short inverted repeats, which shortened the ancestral DNA stepwise. The 26,032-deletion is more ancient. The derived allele is always present in resistant varieties of the ‘Seibel 4614’ lineage, completely absent from V. vinifera, not found in other North American accessions, and rarely present in Asian species. It may have originated in a common ancestral population before the continental disjunction, followed by incomplete lineage sorting, or in either lineage followed by introgression via secondary contacts. Genotyping with these markers does not require special instruments or chemistry for routine screening in breeding practice. Differences in amplicon size between grapes that carry or do not carry Rpv3-1 are detectable via standard agarose gel electrophoresis, or classical melting curve analysis using nonsaturating fluorescent dyes. The recombination rate between each marker and the trait locus is 0.118% for InDel-25,941 and 0.071% for InDel-26,032.     

<Emphasis Type="Italic">Bactrocera oleae</Emphasis> pupae predation by <Emphasis Type="Italic">Ocypus olens</Emphasis> detected by molecular gut content analysis

The pupae of Bactrocera oleae (Diptera: Tephritidae) complete their development during autumn and winter in the soil, rather than in the drupe, resulting susceptible to edaphic predators. Environmentally friendly methods to control this olive pest involve the identification of its natural enemies. This study evaluated the role of Ocypus olens (Coleoptera: Staphylinidae) in the predation of B. oleae pupae, by means of molecular gut content analysis. Modified dry pitfall traps were used to collect live specimens from low-input olive orchards in Tuscany (Italy). Sampling was fine-tuned with a degree-day model estimating the presence of pest pupae in the soil. PCR analyses carried out on field-collected specimens demonstrated that O. olens is a predator of B. oleae, at least during autumn. These results are consistent with predictions of the degree-day model. Knowledge on species composition, traits and complementarity of the natural enemies of B. oleae pupae needs further investigation to advance conservation biological control strategies.     

Identification of regulatory regions within the Ty1 transposable element that regulate iso-2-cytochrome c production in the CYC7-H2 yeast mutant.

The CYC7-H2 mutation in the yeast Saccharomyces cerevisiae was caused by insertion of a Ty1 transposable element in front of the iso-2-cytochrome c structural gene, CYC7. The Ty1 insertion places iso-2-cytochrome c production under control of regulatory signals that are normally required for mating functions in yeast cells. We have investigated the regions of the Ty1 insertion that are responsible for the aberrant production of iso-2-cytochrome c in the CYC7-H2 mutant. Five alterations of the CYC7-H2 gene were obtained by specific restriction endonuclease cleavage of the cloned DNA and ligation of appropriate fragments. The CYC7+, CYC7-H2, and modified CYC7-H2 genes were each inserted into the yeast vector YIp5 and used to transform a cytochrome c-deficient yeast strain. Expression and regulation of each allele integrated at the CYC7 locus have been compared in vivo by determination of the amount of iso-2-cytochrome c produced. These results show that distal regions of the Ty1 element are not essential for the CYC7-H2 overproducing phenotype. In contrast, alterations in the vicinity of the proximal Ty1 junction abolish the CYC7-H2 expression and give rise to different phenotypes.     

The Gene for Hereditary Bullous Dystrophy, X-Linked Macular Type, Maps to the Xq27.3-qter Region

Bullous dystrophy, hereditary macular type (McKusick 302000), is an X-linked disorder and was originally described in a single kindred in the Netherlands by Mendes da Costa and Van der Valk in 1908. To determine the location of the bullous dystrophy gene, segregation studies were performed in this family and in a recently described Italian family. Using informative polymorphic markers, the gene could initially be localized on the Xq27-q28 region. No recombinants were noted with loci in Xq27.3-q28. Fine mapping places the bullous dystrophy locus distal to DXS102 (Xq26.3) in the Italian family and distal to DXS998 (Xq27.3) in the Dutch family.     

Screening for known mutations in the LDL receptor gene causing familial hypercholesterolemia

Familial hypercholesterolemia (FH) is caused by defective low density lipoprotein (LDL) receptors and is characterized by hypercholesterolemia and premature coronary heart disease. Two strategies can be used to identify the mutation in the LDL receptor gene underlying FH. One strategy is to search for novel mutations by DNA sequencing with or without prior mutation screening. The other strategy is to screen for known mutations. In this study we employed the latter strategy to screen 75 unrelated, Norwegian FH subjects for 38 known mutations. Three of the 38 mutations were detected in our group of FH subjects. Two subjects had FH-Padova, one had FH-Cincinnati-2 and one had FH-Gujerat. When additional unrelated FH heterozygotes were screened for the three mutations, the gene frequencies were 1.3%, 1.0% and 3.0%, respectively. In addition to identifying known mutations we also detected a novel stop codon in codon 541 (S541X). We conclude that screening for known mutations in the LDL receptor gene should be used as a complementary strategy to screening for novel mutations in order to understand the molecular genetics of FH.