scholarly journals Plasmids encode niche-specific traits in Lactobacillaceae

2020 ◽  
Author(s):  
Dimple Davray ◽  
Dipti Deo ◽  
Ram Kulkarni

AbstractThe species of family Lactobacillaceae are found in highly diverse environments and play an important role in fermented foods and probiotic products. Many of these species have been individually reported to harbor plasmids that encode important genes. In this study, we performed comparative genomic analysis of the publically available data of 512 plasmids from 282 strains represented by 51 species of this family and correlated the genomic features of plasmids with the ecological niches in which these species are found. Two-third of the species had at least one plasmid-harboring strain. Plasmid abundance and GC content were significantly lower in the vertebrate-adapted species as compared to the nomadic and free-living species. Hierarchical clustering (HCL) highlighted the distinct nature of plasmids from the nomadic and free-living species than those from the vertebrate-adapted species. EggNOG assisted functional annotation revealed that genes associated with transposition, conjugation, DNA repair and recombination, exopolysaccharide production, metal ion transport, toxin-antitoxin system, and stress tolerance were significantly enriched on the plasmids of the nomadic and in some cases nomadic and free-living species. On the other hand, genes related to anaerobic metabolism, ABC transporters, and major facilitator superfamily were found to be overrepresented on the plasmids of the vertebrate-adapted species. These genomic signatures are correlated to the comparatively nutrient-depleted, stressful and dynamic environments of nomadic and free-living species and nutrient-rich and anaerobic environments of the vertebrate-adapted species. Thus, these results indicate the contribution of the plasmids in the adaptation of lactobacilli to the respective habitats. This study also underlines the potential application of these plasmids in improving the technological and probiotic properties of lactic acid bacteria.Impact statementThe bacteria of the family Lactobacillaceae are present in the wide range of habitats and play an important role in human health, fermented foods and chemical industries. A few studies have demonstrated the presence of plasmids in the individual strains of Lactobacillaceae species encoding various traits. Extensive data of genome sequences of the lactobacilli are becoming available; however, no comprehensive analysis of the plasmid-encoded genes and determining their biological relevance across lactobacilli has been undertaken at a larger scale. In this study, we explored the genomic content of 512 plasmids of Lactobacillaceae species and correlated it to the three types of these species according to their ecological niches – vertebrate-adapted, free-living and nomadic. Comparatively lower plasmid abundance and GC content in the vertebrate-adapted species could be correlated to the presence of these species in the nutrient-rich environment. The genomic content of the plasmids was consistent with the respective lifestyle adopted by lactobacilli suggesting that the plasmids might enhance the niche-specific fitness of the strains. The plethora of important genes present on the plasmids can also make them a highly useful tool in improving the probiotic, technological and food-related properties of lactobacilli.Data summaryNucleotide sequences of plasmids of Lactobacillus strains for which complete genome sequences were available were retrieved from the NCBI genome [https://www.ncbi.nlm.nih.gov/genome] and PATRIC 3.5.41 databases on 31st March 2019. The dataset includes 512 nucleotide sequences of plasmids of 282 strains belonging to genus Lactobacillus before its reclassification into several genera (1). Details of the plasmids have been given in Table S1.

2020 ◽  
Author(s):  
Dimple Davray ◽  
Dipti Deo ◽  
Ram Kulkarni

Species belonging to the family Lactobacillaceae are found in highly diverse environments and play an important role in fermented foods and probiotic products. Many of these species have been individually reported to harbour plasmids that encode important genes. In this study, we performed comparative genomic analysis of publicly available data for 512 plasmids from 282 strains represented by 51 species of this family and correlated the genomic features of plasmids with the ecological niches in which these species are found. Two-thirds of the species had at least one plasmid-harbouring strain. Plasmid abundance and GC content were significantly lower in vertebrate-adapted species as compared to nomadic and free-living species. Hierarchical clustering highlighted the distinct nature of plasmids from the nomadic and free-living species than those from the vertebrate-adapted species. EggNOG-assisted functional annotation revealed that genes associated with transposition, conjugation, DNA repair and recombination, exopolysaccharide production, metal ion transport, toxin–antitoxin system, and stress tolerance were significantly enriched on the plasmids of the nomadic and in some cases nomadic and free-living species. On the other hand, genes related to anaerobic metabolism, ABC transporters and the major facilitator superfamily were overrepresented on the plasmids of the vertebrate-adapted species. These genomic signatures correlate with the comparatively nutrient-depleted, stressful and dynamic environments of nomadic and free-living species and nutrient-rich and anaerobic environments of vertebrate-adapted species. Thus, these results indicate the contribution of the plasmids in the adaptation of lactobacilli to their respective habitats. This study also underlines the potential application of these plasmids in improving the technological and probiotic properties of lactic acid bacteria.


2021 ◽  
Vol 53 (4) ◽  
Author(s):  
Jean N. Hakizimana ◽  
Jean B. Ntirandekura ◽  
Clara Yona ◽  
Lionel Nyabongo ◽  
Gladson Kamwendo ◽  
...  

AbstractSeveral African swine fever (ASF) outbreaks in domestic pigs have been reported in Burundi and Malawi and whole-genome sequences of circulating outbreak viruses in these countries are limited. In the present study, complete genome sequences of ASF viruses (ASFV) that caused the 2018 outbreak in Burundi (BUR/18/Rutana) and the 2019 outbreak in Malawi (MAL/19/Karonga) were produced using Illumina next-generation sequencing (NGS) platform and compared with other previously described ASFV complete genomes. The complete nucleotide sequences of BUR/18/Rutana and MAL/19/Karonga were 176,564 and 183,325 base pairs long with GC content of 38.62 and 38.48%, respectively. The MAL/19/Karonga virus had a total of 186 open reading frames (ORFs) while the BUR/18/Rutana strain had 151 ORFs. After comparative genomic analysis, the MAL/19/Karonga virus showed greater than 99% nucleotide identity with other complete nucleotides sequences of p72 genotype II viruses previously described in Tanzania, Europe and Asia including the Georgia 2007/1 isolate. The Burundian ASFV BUR/18/Rutana exhibited 98.95 to 99.34% nucleotide identity with genotype X ASFV previously described in Kenya and in Democratic Republic of the Congo (DRC). The serotyping results classified the BUR/18/Rutana and MAL/19/Karonga ASFV strains in serogroups 7 and 8, respectively. The results of this study provide insight into the genetic structure and antigenic diversity of ASFV strains circulating in Burundi and Malawi. This is important in order to understand the transmission dynamics and genetic evolution of ASFV in eastern Africa, with an ultimate goal of designing an efficient risk management strategy against ASF transboundary spread.


mBio ◽  
2018 ◽  
Vol 9 (3) ◽  
Author(s):  
Yan Wang ◽  
Matt Stata ◽  
Wei Wang ◽  
Jason E. Stajich ◽  
Merlin M. White ◽  
...  

ABSTRACTModern genomics has shed light on many entomopathogenic fungi and expanded our knowledge widely; however, little is known about the genomic features of the insect-commensal fungi. Harpellales are obligate commensals living in the digestive tracts of disease-bearing insects (black flies, midges, and mosquitoes). In this study, we produced and annotated whole-genome sequences of nine Harpellales taxa and conducted the first comparative analyses to infer the genomic diversity within the members of the Harpellales. The genomes of the insect gut fungi feature low (26% to 37%) GC content and large genome size variations (25 to 102 Mb). Further comparisons with insect-pathogenic fungi (from both Ascomycota and Zoopagomycota), as well as with free-living relatives (as negative controls), helped to identify a gene toolbox that is essential to the fungus-insect symbiosis. The results not only narrow the genomic scope of fungus-insect interactions from several thousands to eight core players but also distinguish host invasion strategies employed by insect pathogens and commensals. The genomic content suggests that insect commensal fungi rely mostly on adhesion protein anchors that target digestive system, while entomopathogenic fungi have higher numbers of transmembrane helices, signal peptides, and pathogen-host interaction (PHI) genes across the whole genome and enrich genes as well as functional domains to inactivate the host inflammation system and suppress the host defense. Phylogenomic analyses have revealed that genome sizes of Harpellales fungi vary among lineages with an integer-multiple pattern, which implies that ancient genome duplications may have occurred within the gut of insects.IMPORTANCEInsect guts harbor various microbes that are important for host digestion, immune response, and disease dispersal in certain cases. Bacteria, which are among the primary endosymbionts, have been studied extensively. However, fungi, which are also frequently encountered, are poorly known with respect to their biology within the insect guts. To understand the genomic features and related biology, we produced the whole-genome sequences of nine gut commensal fungi from disease-bearing insects (black flies, midges, and mosquitoes). The results show that insect gut fungi tend to have low GC content across their genomes. By comparing these commensals with entomopathogenic and free-living fungi that have available genome sequences, we found a universal core gene toolbox that is unique and thus potentially important for the insect-fungus symbiosis. This comparative work also uncovered different host invasion strategies employed by insect pathogens and commensals, as well as a model system to study ancient fungal genome duplication within the gut of insects.


2020 ◽  
Author(s):  
Xueping LI ◽  
Jianhong Li ◽  
Yonghong Qi ◽  
Yonggang Liu ◽  
Minquan Li

Abstract BackgroundFusarium equiseti is a plant pathogen with a wide range of hosts and diverse effects, including probiotic activity. However, the underlying molecular mechanisms remain unclear, hindering its effective control and utilization. In this study, the Illumina HiSeq 4000 and PacBio platforms were used to sequence and assemble the whole genome of Fusarium equiseti D25-1.ResultsThe assembly included 16 fragments with a GC content of 48.01%, gap number of zero, and size of 40,776,005 bp. There were 40,110 exons and 26,281 introns having a total size of 19,787,286 bp and 2,290,434 bp, respectively. The genome had an average copy number of 333, 71, 69, 31, and 108 for tRNAs, rRNAs, sRNAs, snRNAs, and miRNAs, respectively. The total repetitive sequence length was 1,713,918 bp, accounting for 4.2033% of the genome. In total, 13,134 functional genes were annotated, accounting for 94.97% of the total gene number. Toxin-related genes, including two related to zearalenone and 23 related to trichothecene, were identified. A comparative genomic analysis supported the high quality of the F. equiseti assembly, exhibiting good collinearity with the reference strains, 3,483 species-specific genes, and 1,805 core genes. A gene family analysis revealed more than 2,500 single-copy orthologs. F. equiseti was most closely related to Fusarium pseudograminearum based on a phylogenetic analysis at the whole-genome level.ConclusionsOur comprehensive analysis of the whole genome of F. equiseti provides basic data for studies of gene expression, regulatory and functional mechanisms, evolutionary processes, as well as disease prevention and control.


2022 ◽  
Vol 12 ◽  
Author(s):  
Eiseul Kim ◽  
Seung-Min Yang ◽  
Dayoung Kim ◽  
Hae-Yeong Kim

Lacticaseibacillus casei, Lacticaseibacillus chiayiensis, and Lacticaseibacillus zeae are very closely related Lacticaseibacillus species. L. casei has long been proposed as a probiotic, whereas studies on functional characterization for L. chiayiensis and L. zeae are some compared to L. casei. In this study, L. casei FBL6, L. chiayiensis FBL7, and L. zeae FBL8 were isolated from raw milk, and their probiotic properties were investigated. Genomic analysis demonstrated the role of L. chiayiensis and L. zeae as probiotic candidates. The three strains were tolerant to acid and bile salt, with inhibitory action against pathogenic bacterial strains and capacity of antioxidants. Complete genome sequences of the three strains were analyzed to highlight the probiotic properties at the genetic level, which results in the discovery of genes corresponding to phenotypic characterization. Moreover, genes known to confer probiotic characteristics were identified, including genes related to biosynthesis, defense machinery, adhesion, and stress adaptation. The comparative genomic analysis with other available genomes revealed 256, 214, and 32 unique genes for FBL6, FBL7, and FBL8, respectively. These genomes contained individual genes encoding proteins that are putatively involved in carbohydrate transport and metabolism, prokaryotic immune system for antiviral defense, and physiological control processes. In particular, L. casei FBL6 had a bacteriocin gene cluster that was not present in other genomes of L. casei, resulting in this strain may exhibit a wide range of antimicrobial activity compared to other L. casei strains. Our data can help us understand the probiotic functionalities of the three strains and suggest that L. chiayiensis and L. zeae species, which are closely related to L. casei, can also be considered as novel potential probiotic candidate strains.


2019 ◽  
Vol 11 (12) ◽  
pp. 3445-3451 ◽  
Author(s):  
Jacqueline Heckenhauer ◽  
Paul B Frandsen ◽  
Deepak K Gupta ◽  
Juraj Paule ◽  
Stefan Prost ◽  
...  

Abstract Members of the speciose insect order Trichoptera (caddisflies) provide important ecosystem services, for example, nutrient cycling through breaking down of organic matter. They are also of industrial interest due to their larval silk secretions. These form the basis for their diverse case-making behavior that allows them to exploit a wide range of ecological niches. Only five genomes of this order have been published thus far, with variable qualities regarding contiguity and completeness. A low-cost sequencing strategy, that is, using a single Oxford Nanopore flow cell per individual along with Illumina sequence reads was successfully used to generate high-quality genomes of two Trichoptera species, Plectrocnemia conspersa and Hydropsyche tenuis. Of the de novo assembly methods compared, assembly of low coverage Nanopore reads (∼18×) and subsequent polishing with long reads followed by Illumina short reads (∼80–170× coverage) yielded the highest genome quality both in terms of contiguity and BUSCO completeness. The presented genomes are the shortest to date and extend our knowledge of genome size across caddisfly families. The genomic region that encodes for light (L)-chain fibroin, a protein component of larval caddisfly silk was identified and compared with existing L-fibroin gene clusters. The new genomic resources presented in this paper are among the highest quality Trichoptera genomes and will increase the knowledge of this important insect order by serving as the basis for phylogenomic and comparative genomic studies.


2020 ◽  
Vol 21 (18) ◽  
pp. 6709
Author(s):  
Katarzyna Bujak ◽  
Przemyslaw Decewicz ◽  
Jerzy Kaminski ◽  
Monika Radlinska

Bacteria of the genus Serratia inhabit a variety of ecological niches like water, soil, and the bodies of animals, and have a wide range of lifestyles. Currently, the complete genome sequences of 25 Serratia phages are available in the NCBI database. All of them were isolated from nutrient-rich environments like sewage, with the use of clinical Serratia strains as hosts. In this study, we identified a novel Serratia myovirus named vB_SspM_BZS1. Both the phage and its host Serratia sp. OS31 were isolated from the same oligotrophic environment, namely, an abandoned gold mine (Zloty Stok, Poland). The BZS1 phage was thoroughly characterized here in terms of its genomics, morphology, and infection kinetics. We also demonstrated that Serratia sp. OS31 was lysogenized by mitomycin-inducible siphovirus vB_SspS_OS31. Comparative analyses revealed that vB_SspM_BZS1 and vB_SspS_OS31 were remote from the known Serratia phages. Moreover, vB_SspM_BZS1 was only distantly related to other viruses. However, we discovered similar prophage sequences in genomes of various bacteria here. Additionally, a protein-based similarity network showed a high diversity of Serratia phages in general, as they were scattered across nineteen different clusters. In summary, this work broadened our knowledge on the diverse relationships of Serratia phages.


Author(s):  
Santiago Fontenla ◽  
Gabriel Rinaldi ◽  
Jose F. Tort

Platyhelminthes comprise one of the major phyla of invertebrate animals, inhabiting a wide range of ecosystems, and one of the most successful in adapting to parasitic life. Small non-coding RNAs have been implicated in regulating complex developmental transitions in model parasitic species. Notably, parasitic flatworms have lost Piwi RNA pathways but gained a novel Argonaute gene. Herein, we analyzed, contrasted and compared the conservation of small RNA pathways among several free-living species (a paraphyletic group traditionally known as ‘turbellarians’) and parasitic species (organized in the monophyletic clade Neodermata) to disentangle possible adaptations during the transition to parasitism. Our findings showed that complete miRNA and RNAi pathways are present in all analyzed free-living flatworms. Remarkably, whilst all ‘turbellarians’ have Piwi proteins, these were lost in parasitic Neodermantans. Moreover, two clusters of Piwi class Argonaute genes are present in all ‘turbellarians’. Interestingly, we identified a divergent Piwi class Argonaute in free living flatworms exclusively, which we named ‘Fliwi’. In addition, other key proteins of the Piwi pathways were conserved in ‘turbellarians’, while none of them were detected in Neodermatans. Besides Piwi and the canonical Argonaute proteins, a flatworm-specific class of Argonautes (FL-Ago) was identified in the analyzed species confirming its ancestrallity to all Platyhelminthes. Remarkably, this clade was expanded in parasitic Neodermatans, but not in free-living species. These phyla-specific Argonautes showed lower sequence conservation compared to other Argonaute proteins, suggesting that they might have been subjected to high evolutionary rates. However, key residues involved in the interaction with the small RNA and mRNA cleavage in the canonical Argonautes were more conserved in the FL-Agos than in the Piwi Argonautes. Whether this is related to specialized functions and adaptations to parasitism in Neodermatans remains unclear. In conclusion, differences detected in gene conservation, sequence and structure of the Argonaute family suggest tentative biological and evolutionary diversifications that are unique to Platyhelminthes. The remarkable divergencies in the small RNA pathways between free-living and parasitic flatworms indicate that they may have been involved in the adaptation to parasitism of Neodermatans.


2019 ◽  
Author(s):  
Ruimin Gao ◽  
Sohail Naushad ◽  
Sylvain Moineau ◽  
Lawrence Goodridge ◽  
Dele Ogunremi

Abstract Background: Bacteriophages are bacterial parasites and are considered the most abundant and diverse biological entities on the planet. Previously we identified 154 prophages from 151 serovars of Salmonella enterica subsp. enterica . A detailed analysis of Salmonella prophage genomics is required given the influence of phages on their bacterial hosts and should provide a broader understanding of Salmonella biology and virulence and contribute to the practical applications of phages as vectors and antibacterial agents. Results: Comparative analysis of the full genome sequences of 142 prophages of Salmonella enterica subsp. enterica retrieved from public databases revealed an extensive variation in genome sizes (6.4- 358.7 kb) and guanine plus cytosine (GC) content (35.5-65.4%) and a linear correlation between the genome size and the number of open reading frames (ORFs). We used three approaches to compare the phage genomes. The NUCmer/MUMmer genome alignment tool was used to evaluate linkages and correlations based on nucleotide identity between genomes. Multiple sequence alignment was performed to calculate genome average nucleotide identity using the Kalgin program. Finally, genome synteny was explored using dot plot analysis. We found that 90 phage genome sequences grouped into 17 distinct clusters while the remaining 52 genomes showed no close relationships with the other phage genomes and are identified as singletons. We generated genome maps using nucleotide and amino acid sequences which allowed protein-coding genes to be sorted into phamilies (phams) using the Phamerator software. Out of 5796 total assigned phamilies, one phamily was observed to be dominant and was found in 49 prophages, or 34.5% of the 142 phages in our collection. A majority of the phamilies, 4330 out of 5796 (74.7%), occurred in just one prophage underscoring the high degree of diversity among Salmonella bacteriophages. Conclusions: Based on nucleotide and amino acid sequences, a high diversity was found among Salmonella bacteriophages which validate the use of prophage sequence analysis as a highly discriminatory subtyping tool for Salmonella. Thorough understanding of the conservation and variation of prophage genomic characteristics will facilitate their rational design and use as tools for bacterial strain construction, vector development and as anti-bacterial agents.


2018 ◽  
Author(s):  
Sarbashis Das ◽  
B. M. Fredrik Pettersson ◽  
Phani Rama Krishna Behra ◽  
Amrita Mallick ◽  
Martin Cheramie ◽  
...  

AbstractMycobacterium marinum is the causative agent for the tuberculosis-like disease mycobacteriosis in fish and skin lesions in humans. Ubiquitous in its geographical distribution, M. marinum is known to occupy diverse fish as hosts. However, information about its genomic diversity is limited. Here, we provide the genome sequences for 15 M. marinum strains isolated from infected humans and fish. Comparative genomic analysis of these and four available genomes of the M. marinum strains M, E11, MB2 and Europe reveal high genomic diversity among the strains, leading to the conclusion that M. marinum should be divided into two different clusters, the “M”- and the “Aronson”-type. We suggest that these two clusters should be considered, if not two separate species, at least two M. marinum subspecies. Our data also show that the M. marinum pan-genome for both groups is open and expanding and we provide data showing high number of mutational hotspots in M. marinum relative to other mycobacteria such as Mycobacterium tuberculosis. This high genomic diversity might be related to that M. marinum occupy different ecological niches.


Sign in / Sign up

Export Citation Format

Share Document