Diversity and Horizontal Transfer of Antarctic Pseudomonas spp. Plasmids

Pseudomonas spp. are widely distributed in various environments around the world. They are also common in the Antarctic regions. To date, almost 200 plasmids of Pseudomonas spp. have been sequenced, but only 12 of them were isolated from psychrotolerant strains. In this study, 15 novel plasmids of cold-active Pseudomonas spp. originating from the King George Island (Antarctica) were characterized using a combined, structural and functional approach, including thorough genomic analyses, functional analyses of selected genetic modules, and identification of active transposable elements localized within the plasmids and comparative genomics. The analyses performed in this study increased the understanding of the horizontal transfer of plasmids found within Pseudomonas populations inhabiting Antarctic soils. It was shown that the majority of the studied plasmids are narrow-host-range replicons, whose transfer across taxonomic boundaries may be limited. Moreover, structural and functional analyses enabled identification and characterization of various accessory genetic modules, including genes encoding major pilin protein (PilA), that enhance biofilm formation, as well as active transposable elements. Furthermore, comparative genomic analyses revealed that the studied plasmids of Antarctic Pseudomonas spp. are unique, as they are highly dissimilar to the other known plasmids of Pseudomonas spp.

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Draft Genome Sequence of Dermatophagoides pteronyssinus, the European House Dust Mite

Genome Announcements ◽

10.1128/genomea.00789-17 ◽

2017 ◽

Vol 5 (32) ◽

Cited By ~ 8

Author(s):

Rose Waldron ◽

Jamie McGowan ◽

Natasha Gordon ◽

Charley McCarthy ◽

E. Bruce Mitchell ◽

...

Keyword(s):

Genome Sequence ◽

Gene Prediction ◽

Draft Genome ◽

Dermatophagoides Pteronyssinus ◽

Mite Species ◽

Draft Genome Sequence ◽

Comparative Genomic ◽

Genomic Analyses ◽

Dust Mite ◽

Functional Analyses

ABSTRACT Dermatophagoides pteronyssinus is the European dust mite and a major source of human allergens. Here, we present the first draft genome sequence of the mite, as well as the ab initio gene prediction and functional analyses that will facilitate comparative genomic analyses with other mite species.

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Comparative genomic and transcriptomic analyses of transposable elements in polychaetous annelids highlight LTR retrotransposon diversity and evolution

Mobile DNA ◽

10.1186/s13100-021-00252-0 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Jonathan Filée ◽

Sarah Farhat ◽

Dominique Higuet ◽

Laure Teysset ◽

Dominique Marie ◽

...

Keyword(s):

Transposable Elements ◽

High Throughput Sequencing ◽

Comparative Genomic ◽

Ltr Retrotransposon ◽

Genomic Evolution ◽

Genome Wide ◽

Genomic Analyses ◽

Different Types ◽

Evolutionary Success ◽

Low Coverage

Abstract Background With the expansion of high throughput sequencing, we now have access to a larger number of genome-wide studies analyzing the Transposable elements (TEs) composition in a wide variety of organisms. However, genomic analyses often remain too limited in number and diversity of species investigated to study in depth the dynamics and evolutionary success of the different types of TEs among metazoans. Therefore, we chose to investigate the use of transcriptomes to describe the diversity of TEs in phylogenetically related species by conducting the first comparative analysis of TEs in two groups of polychaetes and evaluate the diversity of TEs that might impact genomic evolution as a result of their mobility. Results We present a detailed analysis of TEs distribution in transcriptomes extracted from 15 polychaetes depending on the number of reads used during assembly, and also compare these results with additional TE scans on associated low-coverage genomes. We then characterized the clades defined by 1021 LTR-retrotransposon families identified in 26 species. Clade richness was highly dependent on the considered superfamily. Copia elements appear rare and are equally distributed in only three clades, GalEa, Hydra and CoMol. Among the eight BEL/Pao clades identified in annelids, two small clades within the Sailor lineage are new for science. We characterized 17 Gypsy clades of which only 4 are new; the C-clade largely dominates with a quarter of the families. Finally, all species also expressed for the majority two distinct transcripts encoding PIWI proteins, known to be involved in control of TEs mobilities. Conclusions This study shows that the use of transcriptomes assembled from 40 million reads was sufficient to access to the diversity and proportion of the transposable elements compared to those obtained by low coverage sequencing. Among LTR-retrotransposons Gypsy elements were unequivocally dominant but results suggest that the number of Gypsy clades, although high, may be more limited than previously thought in metazoans. For BEL/Pao elements, the organization of clades within the Sailor lineage appears more difficult to establish clearly. The Copia elements remain rare and result from the evolutionary consistent success of the same three clades.

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Insights into the Evolution of Spermatogenesis-Related Ubiquitin–Proteasome System Genes in Abdominal Testicular Laurasiatherians

Genes ◽

10.3390/genes12111780 ◽

2021 ◽

Vol 12 (11) ◽

pp. 1780

Author(s):

Xiaoyue Ding ◽

Li Cao ◽

Yu Zheng ◽

Xu Zhou ◽

Xiaofang He ◽

...

Keyword(s):

Sperm Cell ◽

Rapid Evolution ◽

Ubiquitin Proteasome System ◽

Comparative Genomic ◽

Functional Assays ◽

The Core ◽

Genomic Analyses ◽

Ubiquitin Proteasome ◽

Normal Spermatogenesis ◽

Functional Analyses

During embryonic development in mammals, the testicles generally descend into the scrotum, making the testicular temperature 2–4 °C lower than the core temperature via heat exchange and clearance, and thus more beneficial for normal spermatogenesis. Failure to descend, known as cryptorchidism, carries a series of risks such as infertility and testicular cancer. However, some mammals have evolved abdominal testes while maintaining healthy reproduction. To explore the underlying molecular mechanism, we conducted comparative genomic analyses and functional assays on the spermatogenesis-related ubiquitin–proteasome system (UPS) genes essential to sperm formation in representative laurasiatherians. Here, positive selection and rapid evolution of spermatogenesis-related UPS genes were identified in the abdominal testicular laurasiatherians. Moreover, potential convergent amino acids were found between distantly related species with similar abdominal testicles and functional analyses showed RNF8 (V437I) in abdominal testicular species (437I) has a stronger ubiquitination ability, which suggests that the mammals with abdominal testes might exhibit enhanced sperm cell histone clearance to maintain sperm formation. This evidence implies that, in response to “cryptorchidism injury”, spermatogenesis-related UPS genes in the abdominal testicular species might have undergone adaptive evolution to stabilize sperm formation. Thus, our study could provide some novel insights into the reproductive adaptation in abdominal testicular mammals.

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Genome Sequencing Analysis of Scleromitrula shiraiana, a Causal Agent of Mulberry Sclerotial Disease With Narrow Host Range

Frontiers in Microbiology ◽

10.3389/fmicb.2020.603927 ◽

2021 ◽

Vol 11 ◽

Author(s):

Zhiyuan Lv ◽

Ziwen He ◽

Lijuan Hao ◽

Xin Kang ◽

Bi Ma ◽

...

Keyword(s):

Host Range ◽

Molecular Mechanisms ◽

Genomic Analysis ◽

Effector Proteins ◽

Ecological Niches ◽

Comparative Genomic ◽

Sequencing Analysis ◽

Cell Wall Degrading Enzymes ◽

Narrow Host Range ◽

Genes Encoding

Scleromitrula shiraiana is a necrotrophic fungus with a narrow host range, and is one of the main causal pathogens of mulberry sclerotial disease. However, its molecular mechanisms and pathogenesis are unclear. Here, we report a 39.0 Mb high-quality genome sequence for S. shiraiana strain SX-001. The S. shiraiana genome contains 11,327 protein-coding genes. The number of genes and genome size of S. shiraiana are similar to most other Ascomycetes. The cross-similarities and differences of S. shiraiana with the closely related Sclerotinia sclerotiorum and Botrytis cinerea indicated that S. shiraiana differentiated earlier from their common ancestor. A comparative genomic analysis showed that S. shiraiana has fewer genes encoding cell wall-degrading enzymes (CWDEs) and effector proteins than that of S. sclerotiorum and B. cinerea, as well as many other Ascomycetes. This is probably a key factor in the weaker aggressiveness of S. shiraiana to other plants. S. shiraiana has many species-specific genes encoding secondary metabolism core enzymes. The diversity of secondary metabolites may be related to the adaptation of these pathogens to specific ecological niches. However, melanin and oxalic acid are conserved metabolites among many Sclerotiniaceae fungi, and may be essential for survival and infection. Our results provide insights into the narrow host range of S. shiraiana and its adaptation to mulberries.

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Comparative genomic analyses of two novel qnrVC6 carrying multidrug-resistant Pseudomonas. spp strains

Microbial Pathogenesis ◽

10.1016/j.micpath.2018.07.026 ◽

2018 ◽

Vol 123 ◽

pp. 269-274 ◽

Cited By ~ 2

Author(s):

Junyan Liu ◽

Ling Yang ◽

Lin Li ◽

Bing Li ◽

Dingqiang Chen ◽

...

Keyword(s):

Multidrug Resistant ◽

Comparative Genomic ◽

Pseudomonas Spp ◽

Genomic Analyses

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Pathogenic Determinants of the Mycobacterium kansasii Complex: An Unsuspected Role for Distributive Conjugal Transfer

Microorganisms ◽

10.3390/microorganisms9020348 ◽

2021 ◽

Vol 9 (2) ◽

pp. 348

Author(s):

Florian Tagini ◽

Trestan Pillonel ◽

Claire Bertelli ◽

Katia Jaton ◽

Gilbert Greub

Keyword(s):

Genomic Analysis ◽

Comparative Genomic ◽

Mycobacterium Kansasii ◽

Type Vii Secretion ◽

A Genome ◽

Genes Encoding ◽

Associated Proteins ◽

Immunosuppressed Patients ◽

Type Vii Secretion System ◽

Clinical Records

The Mycobacterium kansasii species comprises six subtypes that were recently classified into six closely related species; Mycobacterium kansasii (formerly M. kansasii subtype 1), Mycobacterium persicum (subtype 2), Mycobacterium pseudokansasii (subtype 3), Mycobacterium ostraviense (subtype 4), Mycobacterium innocens (subtype 5) and Mycobacterium attenuatum (subtype 6). Together with Mycobacterium gastri, they form the M. kansasii complex. M. kansasii is the most frequent and most pathogenic species of the complex. M. persicum is classically associated with diseases in immunosuppressed patients, and the other species are mostly colonizers, and are only very rarely reported in ill patients. Comparative genomics was used to assess the genetic determinants leading to the pathogenicity of members of the M. kansasii complex. The genomes of 51 isolates collected from patients with and without disease were sequenced and compared with 24 publicly available genomes. The pathogenicity of each isolate was determined based on the clinical records or public metadata. A comparative genomic analysis showed that all M. persicum, M. ostraviense, M innocens and M. gastri isolates lacked the ESX-1-associated EspACD locus that is thought to play a crucial role in the pathogenicity of M. tuberculosis and other non-tuberculous mycobacteria. Furthermore, M. kansasii was the only species exhibiting a 25-Kb-large genomic island encoding for 17 type-VII secretion system-associated proteins. Finally, a genome-wide association analysis revealed that two consecutive genes encoding a hemerythrin-like protein and a nitroreductase-like protein were significantly associated with pathogenicity. These two genes may be involved in the resistance to reactive oxygen and nitrogen species, a required mechanism for the intracellular survival of bacteria. Three non-pathogenic M. kansasii lacked these genes likely due to two distinct distributive conjugal transfers (DCTs) between M. attenuatum and M. kansasii, and one DCT between M. persicum and M. kansasii. To our knowledge, this is the first study linking DCT to reduced pathogenicity.

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Genome Reduction and Secondary Metabolism of the Marine Sponge-Associated Cyanobacterium Leptothoe

Marine Drugs ◽

10.3390/md19060298 ◽

2021 ◽

Vol 19 (6) ◽

pp. 298

Author(s):

Despoina Konstantinou ◽

Rafael V. Popin ◽

David P. Fewer ◽

Kaarina Sivonen ◽

Spyros Gkelis

Keyword(s):

Natural Products ◽

Microbial Communities ◽

Genomic Analysis ◽

Gene Clusters ◽

Marine Sponges ◽

Genome Reduction ◽

Extracellular Polysaccharides ◽

Comparative Genomic ◽

Symbiotic Relationships ◽

Genes Encoding

Sponges form symbiotic relationships with diverse and abundant microbial communities. Cyanobacteria are among the most important members of the microbial communities that are associated with sponges. Here, we performed a genus-wide comparative genomic analysis of the newly described marine benthic cyanobacterial genus Leptothoe (Synechococcales). We obtained draft genomes from Le. kymatousa TAU-MAC 1615 and Le. spongobia TAU-MAC 1115, isolated from marine sponges. We identified five additional Leptothoe genomes, host-associated or free-living, using a phylogenomic approach, and the comparison of all genomes showed that the sponge-associated strains display features of a symbiotic lifestyle. Le. kymatousa and Le. spongobia have undergone genome reduction; they harbored considerably fewer genes encoding for (i) cofactors, vitamins, prosthetic groups, pigments, proteins, and amino acid biosynthesis; (ii) DNA repair; (iii) antioxidant enzymes; and (iv) biosynthesis of capsular and extracellular polysaccharides. They have also lost several genes related to chemotaxis and motility. Eukaryotic-like proteins, such as ankyrin repeats, playing important roles in sponge-symbiont interactions, were identified in sponge-associated Leptothoe genomes. The sponge-associated Leptothoe stains harbored biosynthetic gene clusters encoding novel natural products despite genome reduction. Comparisons of the biosynthetic capacities of Leptothoe with chemically rich cyanobacteria revealed that Leptothoe is another promising marine cyanobacterium for the biosynthesis of novel natural products.

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The domestication of Cucurbita argyrosperma as revealed by the genome of its wild relative

Horticulture Research ◽

10.1038/s41438-021-00544-9 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Josué Barrera-Redondo ◽

Guillermo Sánchez-de la Vega ◽

Jonás A. Aguirre-Liguori ◽

Gabriela Castellanos-Morales ◽

Yocelyn T. Gutiérrez-Guerrero ◽

...

Keyword(s):

Defense Mechanisms ◽

Population Level ◽

Growth Hormones ◽

Comparative Genomic ◽

Structural Variants ◽

Closely Related Species ◽

Level Data ◽

Genomic Analyses ◽

Genotype By Sequencing ◽

Regulation Of Growth

AbstractDespite their economic importance and well-characterized domestication syndrome, the genomic impact of domestication and the identification of variants underlying the domestication traits in Cucurbita species (pumpkins and squashes) is currently lacking. Cucurbita argyrosperma, also known as cushaw pumpkin or silver-seed gourd, is a Mexican crop consumed primarily for its seeds rather than fruit flesh. This makes it a good model to study Cucurbita domestication, as seeds were an essential component of early Mesoamerican diet and likely the first targets of human-guided selection in pumpkins and squashes. We obtained population-level data using tunable Genotype by Sequencing libraries for 192 individuals of the wild and domesticated subspecies of C. argyrosperma across Mexico. We also assembled the first high-quality wild Cucurbita genome. Comparative genomic analyses revealed several structural variants and presence/absence of genes related to domestication. Our results indicate a monophyletic origin of this domesticated crop in the lowlands of Jalisco. We found evidence of gene flow between the domesticated and wild subspecies, which likely alleviated the effects of the domestication bottleneck. We uncovered candidate domestication genes that are involved in the regulation of growth hormones, plant defense mechanisms, seed development, and germination. The presence of shared selected alleles with the closely related species Cucurbita moschata suggests domestication-related introgression between both taxa.

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Complete chloroplast genomes of Leptodermis scabrida complex: comparative genomic analyses and phylogenetic relationships

Gene ◽

10.1016/j.gene.2021.145715 ◽

2021 ◽

pp. 145715

Author(s):

Ying Zhang ◽

Zhengfeng Wang ◽

Yanan Guo ◽

Sheng Chen ◽

Xianyi Xu ◽

...

Keyword(s):

Phylogenetic Relationships ◽

Comparative Genomic ◽

Chloroplast Genomes ◽

Genomic Analyses

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Evidence from comparative genomic analyses indicating that Lactobacillus-mediated irritable bowel syndrome alleviation is mediated by the conjugated linoleic acid synthesis

Food & Function ◽

10.1039/d0fo02616f ◽

2021 ◽

Author(s):

Yang Liu ◽

Wei Xiao ◽

Leilei Yu ◽

Fengwei Tian ◽

Gang Wang ◽

...

Keyword(s):

Irritable Bowel Syndrome ◽

Linoleic Acid ◽

Gut Microbiota ◽

Acid Synthesis ◽

Comparative Genomic ◽

Low Grade ◽

Genomic Analyses ◽

Irritable Bowel ◽

Low Grade Inflammation ◽

Gut Microbiota Dysbiosis

Irritable bowel syndrome (IBS) is a chronic intestinal disorder accompanied by low-grade inflammation, visceral hypersensitivity, and gut microbiota dysbiosis. Several studies have indicated that Lactobacillus supplementation can help to alleviate...

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