scholarly journals The Landscape of Recombination Events That Create Nonribosomal Peptide Diversity

2021 ◽  
Author(s):  
Martin Baunach ◽  
Somak Chowdhury ◽  
Pierre Stallforth ◽  
Elke Dittmann
Keyword(s):  
Microbial Ecology ◽  
Structural Diversity ◽  
Selectivity Filter ◽  
Nonribosomal Peptides ◽  
Nonribosomal Peptide ◽  
Bacterial Phyla ◽  
Multienzyme Complexes ◽  
Key Driver ◽  
Structural Diversification

Abstract Nonribosomal peptides (NRP) are crucial molecular mediators in microbial ecology and provide indispensable drugs. Nevertheless, the evolution of the flexible biosynthetic machineries that correlates with the stunning structural diversity of NRPs is poorly understood. Here, we show that recombination is a key driver in the evolution of bacterial NRP synthetase (NRPS) genes across distant bacterial phyla, which has guided structural diversification in a plethora of NRP families by extensive mixing and matching of biosynthesis genes. The systematic dissection of a large number of individual recombination events did not only unveil a striking plurality in the nature and origin of the exchange units but allowed the deduction of overarching principles that enable the efficient exchange of adenylation (A) domain substrates while keeping the functionality of the dynamic multienzyme complexes. In the majority of cases, recombination events have targeted variable portions of the Acore domains, yet domain interfaces and the flexible Asub domain remained untapped. Our results strongly contradict the widespread assumption that adenylation and condensation (C) domains coevolve and significantly challenge the attributed role of C domains as stringent selectivity filter during NRP synthesis. Moreover, they teach valuable lessons on the choice of natural exchange units in the evolution of NRPS diversity, which may guide future engineering approaches.

scholarly journals Nanopore-Sequencing Characterization of the Gut Microbiota of Melolontha melolontha Larvae: Contribution to Protection against Entomopathogenic Nematodes?

Pathogens ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 396
Author(s):  
Ewa Sajnaga ◽  
Marcin Skowronek ◽  
Agnieszka Kalwasińska ◽  
Waldemar Kazimierczak ◽  
Karolina Ferenc ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Entomopathogenic Nematodes ◽  
Bacterial Species ◽  
Antagonistic Activity ◽  
Rrna Gene ◽  
Nanopore Sequencing ◽  
Bacterial Phyla ◽  
Melolontha Melolontha

This study focused on the potential relationships between midgut microbiota of the common cockchafer Melolontha melolontha larvae and their resistance to entomopathogenic nematodes (EPN) infection. We investigated the bacterial community associated with control and unsusceptible EPN-exposed insects through nanopore sequencing of the 16S rRNA gene. Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetes were the most abundant bacterial phyla within the complex and variable midgut microbiota of the wild M. melolontha larvae. The core microbiota was found to include 82 genera, which accounted for 3.4% of the total number of identified genera. The EPN-resistant larvae differed significantly from the control ones in the abundance of many genera belonging to the Actinomycetales, Rhizobiales, and Clostridiales orders. Additionally, the analysis of the microbiome networks revealed different sets of keystone midgut bacterial genera between these two groups of insects, indicating differences in the mutual interactions between bacteria. Finally, we detected Xenorhabdus and Photorhabdus as gut residents and various bacterial species exhibiting antagonistic activity against these entomopathogens. This study paves the way to further research aimed at unravelling the role of the host gut microbiota on the output of EPN infection, which may contribute to enhancement of the efficiency of nematodes used in eco-friendly pest management.

Role of aromatic dicarboxylates in the structural diversity of cobalt(ii) and copper(ii) coordination polymers containing a flexible N,N′-di(3-pyridyl)octanediamide ligand

CrystEngComm ◽  
2013 ◽  
Vol 15 (36) ◽  
pp. 7274 ◽  
Author(s):  
Xiu-Li Wang ◽  
Fang-Fang Sui ◽  
Hong-Yan Lin ◽  
Chuang Xu ◽  
Guo-Cheng Liu ◽  
...  
Keyword(s):  
Coordination Polymers ◽  
Structural Diversity

scholarly journals Bacteriocin-like activity of oral Fusobacterium nucleatum isolated from human and non-human primates

1999 ◽  
Vol 30 (4) ◽  
pp. 324-346 ◽  
Author(s):  
Elerson Gaetti-Jardim Júnior ◽  
Mario Julio Avila-Campos
Keyword(s):  
Oral Cavity ◽  
Microbial Ecology ◽  
Dental Plaque ◽  
Fusobacterium Nucleatum ◽  
Antagonistic Activity ◽  
Healthy Individuals ◽  
Bacterial Microbiota ◽  
Reference Strains

Fusobacterium nucleatum is indigenous of the human oral cavity and has been involved in different infectious processes. The production of bacteriocin-like substances may be important in regulation of bacterial microbiota in oral cavity. The ability to produce bacteriocin-like substances by 80 oral F. nucleatum isolates obtained from periodontal patients, healthy individuals and Cebus apella monkeys, was examinated. 17.5% of all tested isolates showed auto-antagonism and 78.8% iso- or hetero-antagonism. No isolate from monkey was capable to produce auto-inhibition. In this study, the antagonistic substances production was variable in all tested isolates. Most of the F. nucleatum showed antagonistic activity against tested reference strains. These data suggest a possible participation of these substances on the oral microbial ecology in humans and animals. However, the role of bacteriocins in regulating dental plaque microbiota in vivo is discussed.

scholarly journals A hidden catalysis: metal-, and organocatalyst-free one-pot assembly of chiral aza-tricyclic molecules containing six contiguous stereocenters

2020 ◽  
Author(s):  
Dung Do
Keyword(s):  
Chemical Space ◽  
Structural Diversity ◽  
Therapeutic Agents ◽  
Chiral Molecules ◽  
One Pot ◽  
Complex Molecules ◽  
Chiral Complex ◽  
Enamine Catalysis ◽  
Daunting Challenge

<p></p><p>Chiral molecules with their defined 3-D structures are of paramount importance for the study of chemical biology and drug discovery. Having rich structural diversity and unique stereoisomerism, chiral molecules offer a large chemical space that can be explored for the design of new therapeutic agents.<sup>1</sup> In practice, chiral architectures are usually prepared from organometallic and organocatalytic processes where a transition metal or an organocatalyst is tailor-made for a desired reaction. As a result, developing a method that enables rapid assembly of chiral complex molecules under a metal- and organocatalyst-free condition represents a daunting challenge. Here we developed a straightforward one-pot procedure to create a chiral 3-D structure from 2-D structures and an amino acid without any chiral catalyst. The center of this research is the design of a <a>special chiral spiroimidazolidinone cyclohexadienone intermediate</a>, a merger of a chiral reactive substrate with multiple nucleophillic/electrophillic sites and a transient organocatalyst. <a>This unique substrate-catalyst (“sub-catalyst”) dual role of the intermediate was displayed in its aza-Michael/Michael cascade reaction with an </a>α,β-unsaturated aldehyde under an iminium/enamine catalysis. <a>The enhanced co-ordinational proximity of the chiral substrate and catalyst</a> in the transition state resulted in a substantial steric discrimination and an excellent overall diastereoselectivity. Aza-tricylic molecules with six contiguous stereocenters were assembled from <i>N</i>-alkylated aminophenols, α,β-unsaturated aldehydes and chiral α-amino acids under a hidden “sub-catalysis” where the strategically produced “sub-catalyst” does not present in initial components of the reaction. The success of this methodology will pave the way for many efficient preparations of chiral complex molecules.</p><br><p></p>

scholarly journals Dietary taste patterns by sex and weight status in the Netherlands

2018 ◽  
Vol 119 (10) ◽  
pp. 1195-1206 ◽  
Author(s):  
Astrid W. B. van Langeveld ◽  
Pey Sze Teo ◽  
Jeanne H. M. de Vries ◽  
Edith J. M. Feskens ◽  
Cees de Graaf ◽  
...  
Keyword(s):  
The Netherlands ◽  
Observational Study ◽  
Food Choice ◽  
Weight Status ◽  
Normal Weight ◽  
Taste Preferences ◽  
Food Consumption Survey ◽  
Key Driver ◽  
Consumption Survey

AbstractTaste is a key driver of food choice and intake. Taste preferences are widely studied, unlike the diet’s taste profile. This study assessed dietary taste patterns in the Netherlands by sex, BMI, age and education. A taste database, containing 476 foods’ taste values, was combined with 2-d 24-h recalls in two study populations. The percentage of energy intake from six taste clusters was assessed in the Dutch National Food Consumption Survey (DNFCS 2007–2010; n 1351) and in an independent observational study: the Nutrition Questionnaires plus (NQplus) study (2011–2013; n 944). Dietary taste patterns were similar across study populations. Men consumed relatively more energy from ‘salt, umami and fat’ (DNFCS; 24 % energy, NQplus study; 23 %)- and ‘bitter’ (7 %)-tasting foods compared with women (21 %, P<0·001, 22 %, P=0·005; 3 %, P<0·001, 4 %, P<0·001, respectively). Women consumed more % energy from ‘sweet and fat’ (15 %)- and ‘sweet and sour’ (13 %, 12 %, respectively)-tasting foods compared with men (12 %, P<0·001, 13 %, P=0·001; 10 %, P<0·001). Obese individuals consumed more % energy from ‘salt, umami and fat’- and less from ‘sweet and fat’-tasting foods than normal-weight individuals (‘salt, umami and fat’, men; obese both studies 26 %, normal-weight DNFCS 23 %, P=0·037, NQplus 22 %, P=0·001, women; obese 23 %, 24 %, normal weight 20 %, P=0·004, P=0·011, respectively, ‘sweet and fat’, men; obese 11 %, 10 %, normal weight 13 %, P<0·05, 14 %, P<0·01, women; obese 14 %, 15 %, normal weight 16 %, P=0·12, P=0·99). In conclusion, our taste database can be used to deepen our understanding of the role of taste in dietary intake in the Netherlands by sex, BMI, age and education.

A Private Tree By-Law’s Contribution to Maintaining a Diverse Urban Forest: Exploring Homeowners’ Replanting Compliance and the Role of Construction Activities in Toronto, Canada

2022 ◽  
Vol 48 (1) ◽  
pp. 9-26
Author(s):  
Tenley Conway ◽  
Jihan Khatib ◽  
Janele Tetreult ◽  
Andrew Almas
Keyword(s):  
Urban Forest ◽  
Good Health ◽  
Diverse Species ◽  
Tree Survival ◽  
Property Owners ◽  
Construction Activity ◽  
Key Driver

Many municipalities are working to protect and grow their urban forest, including adopting private tree regulations. Such regulations typically require property-owners to apply for a permit to remove trees and, if the permit is granted, plant replacement trees. Even with such regulations, many private trees are removed each year, particularly on residential property. Property-level construction activity, including expanding building footprints, replacing an older home with a new one, and increasing hardscaping, is emerging as a key driver of residential tree loss. This study addresses whether homeowners who receive a permit to remove one or more trees comply with the requirement to plant replacement trees to better understand the effect of private tree regulation. We explore this question through a written survey of homeowners who received a tree removal permit and site visits in Toronto (Ontario, Canada). While 70% of all survey participants planted the required replacement trees 2 to 3 years after receiving the permit, only 54% of homeowners whose permit was associated with construction planted. Additionally, most replacement trees were in good health but were dominated by a few genera. We also found significant differences in replacement planting and tree survival across the city’s 4 management districts. This study highlights that if resources supporting private tree regulations are limited, tree permits associated with construction should be prioritized for follow-up. Additionally, guidance about diverse species to plant should be communicated to ensure that private tree regulations are supporting the long-term protection of the urban forest.

On IT-Modelling in a Cross-Competence World

2011 ◽  
pp. 349-359
Author(s):  
Arne Sølvberg
Keyword(s):  
Information Technology ◽  
Technological Change ◽  
Deep Penetration ◽  
Application Domain ◽  
Domain Models ◽  
Key Driver ◽  
Role Of It ◽  
The Relationship ◽  
Competence Models

The deep penetration of computers in all realms of society makes technological change the key driver for changing our lives. This will result in a change in approach, from viewing the role of IT as mainly supporting other disciplines, to the integration of IT concepts, tools and theory into modelling theories of the supported disciplines. This chapter discusses some aspects of the relationship between the IT as a modelling discipline, and the modelling disciplines of the domains where IT is applied. IT deals with data and data processes, while application domain models deal with entities of the domain and how they interact. Cross-competence models must deal with both, and with how models of the information technology discipline relate to the various models of the domain disciplines.

scholarly journals Effects of atrazine on the black community land function and role of microbial ecology

2020 ◽  
Vol 446 ◽  
pp. 032093
Author(s):  
Yaosheng Zhang ◽  
Long Tian ◽  
Ruixi Ma ◽  
Yanxiang Wei ◽  
Jiali Yang ◽  
...  
Keyword(s):  
Microbial Ecology ◽  
Black Community
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