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Gifford DR, Bhattacharyya A, Geim A, Marshall E, Krašovec R, Knight CG. Environmental and genetic influence on the rate and spectrum of spontaneous mutations in Escherichia coli. MICROBIOLOGY (READING, ENGLAND) 2024; 170:001452. [PMID: 38687010 PMCID: PMC11084559 DOI: 10.1099/mic.0.001452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 03/19/2024] [Indexed: 05/02/2024]
Abstract
Spontaneous mutations are the ultimate source of novel genetic variation on which evolution operates. Although mutation rate is often discussed as a single parameter in evolution, it comprises multiple distinct types of changes at the level of DNA. Moreover, the rates of these distinct changes can be independently influenced by genomic background and environmental conditions. Using fluctuation tests, we characterized the spectrum of spontaneous mutations in Escherichia coli grown in low and high glucose environments. These conditions are known to affect the rate of spontaneous mutation in wild-type MG1655, but not in a ΔluxS deletant strain - a gene with roles in both quorum sensing and the recycling of methylation products used in E. coli's DNA repair process. We find an increase in AT>GC transitions in the low glucose environment, suggesting that processes relating to the production or repair of this mutation could drive the response of overall mutation rate to glucose concentration. Interestingly, this increase in AT>GC transitions is maintained by the glucose non-responsive ΔluxS deletant. Instead, an elevated rate of GC>TA transversions, more common in a high glucose environment, leads to a net non-responsiveness of overall mutation rate for this strain. Our results show how relatively subtle changes, such as the concentration of a carbon substrate or loss of a regulatory gene, can substantially influence the amount and nature of genetic variation available to selection.
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Affiliation(s)
- Danna R. Gifford
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Anish Bhattacharyya
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Alexandra Geim
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
- Pembroke College, University of Cambridge, Cambridge, UK
| | - Eleanor Marshall
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Rok Krašovec
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Christopher G. Knight
- Department of Earth and Environmental Sciences, School of Natural Sciences, Faculty of Science and Engineering, The University of Manchester, Manchester, UK
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Coevolution of Metabolic Pathways in Blattodea and Their Blattabacterium Endosymbionts, and Comparisons with Other Insect-Bacteria Symbioses. Microbiol Spectr 2022; 10:e0277922. [PMID: 36094208 PMCID: PMC9603385 DOI: 10.1128/spectrum.02779-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Many insects harbor bacterial endosymbionts that supply essential nutrients and enable their hosts to thrive on a nutritionally unbalanced diet. Comparisons of the genomes of endosymbionts and their insect hosts have revealed multiple cases of mutually-dependent metabolic pathways that require enzymes encoded in 2 genomes. Complementation of metabolic reactions at the pathway level has been described for hosts feeding on unbalanced diets, such as plant sap. However, the level of collaboration between symbionts and hosts that feed on more variable diets is largely unknown. In this study, we investigated amino acid and vitamin/cofactor biosynthetic pathways in Blattodea, which comprises cockroaches and termites, and their obligate endosymbiont Blattabacterium cuenoti (hereafter Blattabacterium). In contrast to other obligate symbiotic systems, we found no clear evidence of "collaborative pathways" for amino acid biosynthesis in the genomes of these taxa, with the exception of collaborative arginine biosynthesis in 2 taxa, Cryptocercus punctulatus and Mastotermes darwiniensis. Nevertheless, we found that several gaps specific to Blattabacterium in the folate biosynthetic pathway are likely to be complemented by their host. Comparisons with other insects revealed that, with the exception of the arginine biosynthetic pathway, collaborative pathways for essential amino acids are only observed in phloem-sap feeders. These results suggest that the host diet is an important driving factor of metabolic pathway evolution in obligate symbiotic systems. IMPORTANCE The long-term coevolution between insects and their obligate endosymbionts is accompanied by increasing levels of genome integration, sometimes to the point that metabolic pathways require enzymes encoded in two genomes, which we refer to as "collaborative pathways". To date, collaborative pathways have only been reported from sap-feeding insects. Here, we examined metabolic interactions between cockroaches, a group of detritivorous insects, and their obligate endosymbiont, Blattabacterium, and only found evidence of collaborative pathways for arginine biosynthesis. The rarity of collaborative pathways in cockroaches and Blattabacterium contrasts with their prevalence in insect hosts feeding on phloem-sap. Our results suggest that host diet is a factor affecting metabolic integration in obligate symbiotic systems.
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Jackson R, Monnin D, Patapiou PA, Golding G, Helanterä H, Oettler J, Heinze J, Wurm Y, Economou CK, Chapuisat M, Henry LM. Convergent evolution of a labile nutritional symbiosis in ants. THE ISME JOURNAL 2022; 16:2114-2122. [PMID: 35701539 PMCID: PMC9381600 DOI: 10.1038/s41396-022-01256-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 05/23/2022] [Accepted: 05/26/2022] [Indexed: 01/07/2023]
Abstract
Ants are among the most successful organisms on Earth. It has been suggested that forming symbioses with nutrient-supplementing microbes may have contributed to their success, by allowing ants to invade otherwise inaccessible niches. However, it is unclear whether ants have evolved symbioses repeatedly to overcome the same nutrient limitations. Here, we address this question by comparing the independently evolved symbioses in Camponotus, Plagiolepis, Formica and Cardiocondyla ants. Our analysis reveals the only metabolic function consistently retained in all of the symbiont genomes is the capacity to synthesise tyrosine. We also show that in certain multi-queen lineages that have co-diversified with their symbiont for millions of years, only a fraction of queens carry the symbiont, suggesting ants differ in their colony-level reliance on symbiont-derived resources. Our results imply that symbioses can arise to solve common problems, but hosts may differ in their dependence on symbionts, highlighting the evolutionary forces influencing the persistence of long-term endosymbiotic mutualisms.
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Affiliation(s)
- Raphaella Jackson
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, E1 4NS, UK
| | - David Monnin
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, E1 4NS, UK
| | - Patapios A Patapiou
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, E1 4NS, UK
- Department of Pathobiology and Population Sciences, Royal Veterinary College, Hatfield, AL9 7TA, UK
| | - Gemma Golding
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, E1 4NS, UK
| | - Heikki Helanterä
- Ecology and Genetics Research Unit, University of Oulu, Oulu, 90014, Finland
- Tvärminne Zoological Station, University of Helsinki, Hanko, Finland
| | - Jan Oettler
- Zoology/Evolutionary Biology, University of Regensburg, Regensburg, 93040, Germany
| | - Jürgen Heinze
- Zoology/Evolutionary Biology, University of Regensburg, Regensburg, 93040, Germany
| | - Yannick Wurm
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, E1 4NS, UK
- Alan Turing Institute, London, NW1 2DB, UK
| | - Chloe K Economou
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, E1 4NS, UK
| | - Michel Chapuisat
- Department of Ecology and Evolution, University of Lausanne, 1015, Lausanne, Switzerland
| | - Lee M Henry
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, E1 4NS, UK.
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4
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Sielemann K, Pucker B, Schmidt N, Viehöver P, Weisshaar B, Heitkam T, Holtgräwe D. Complete pan-plastome sequences enable high resolution phylogenetic classification of sugar beet and closely related crop wild relatives. BMC Genomics 2022; 23:113. [PMID: 35139817 PMCID: PMC8830136 DOI: 10.1186/s12864-022-08336-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 01/20/2022] [Indexed: 12/24/2022] Open
Abstract
Background As the major source of sugar in moderate climates, sugar-producing beets (Beta vulgaris subsp. vulgaris) have a high economic value. However, the low genetic diversity within cultivated beets requires introduction of new traits, for example to increase their tolerance and resistance attributes – traits that often reside in the crop wild relatives. For this, genetic information of wild beet relatives and their phylogenetic placements to each other are crucial. To answer this need, we sequenced and assembled the complete plastome sequences from a broad species spectrum across the beet genera Beta and Patellifolia, both embedded in the Betoideae (order Caryophyllales). This pan-plastome dataset was then used to determine the wild beet phylogeny in high-resolution. Results We sequenced the plastomes of 18 closely related accessions representing 11 species of the Betoideae subfamily and provided high-quality plastome assemblies which represent an important resource for further studies of beet wild relatives and the diverse plant order Caryophyllales. Their assembly sizes range from 149,723 bp (Beta vulgaris subsp. vulgaris) to 152,816 bp (Beta nana), with most variability in the intergenic sequences. Combining plastome-derived phylogenies with read-based treatments based on mitochondrial information, we were able to suggest a unified and highly confident phylogenetic placement of the investigated Betoideae species. Our results show that the genus Beta can be divided into the two clearly separated sections Beta and Corollinae. Our analysis confirms the affiliation of B. nana with the other Corollinae species, and we argue against a separate placement in the Nanae section. Within the Patellifolia genus, the two diploid species Patellifolia procumbens and Patellifolia webbiana are, regarding the plastome sequences, genetically more similar to each other than to the tetraploid Patellifolia patellaris. Nevertheless, all three Patellifolia species are clearly separated. Conclusion In conclusion, our wild beet plastome assemblies represent a new resource to understand the molecular base of the beet germplasm. Despite large differences on the phenotypic level, our pan-plastome dataset is highly conserved. For the first time in beets, our whole plastome sequences overcome the low sequence variation in individual genes and provide the molecular backbone for highly resolved beet phylogenomics. Hence, our plastome sequencing strategy can also guide genomic approaches to unravel other closely related taxa. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-022-08336-8.
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Affiliation(s)
- Katharina Sielemann
- Genetics and Genomics of Plants, Center for Biotechnology (CeBiTec) & Faculty of Biology, Bielefeld University, 33615, Bielefeld, Germany.,Graduate School DILS, Bielefeld Institute for Bioinformatics Infrastructure (BIBI), Bielefeld University, 33615, Bielefeld, Germany
| | - Boas Pucker
- Genetics and Genomics of Plants, Center for Biotechnology (CeBiTec) & Faculty of Biology, Bielefeld University, 33615, Bielefeld, Germany.,Evolution and Diversity, Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK.,Institute of Plant Biology, TU Braunschweig, Braunschweig, Germany
| | - Nicola Schmidt
- Faculty of Biology, Institute of Botany, Technische Universität Dresden, 01069, Dresden, Germany
| | - Prisca Viehöver
- Genetics and Genomics of Plants, Center for Biotechnology (CeBiTec) & Faculty of Biology, Bielefeld University, 33615, Bielefeld, Germany
| | - Bernd Weisshaar
- Genetics and Genomics of Plants, Center for Biotechnology (CeBiTec) & Faculty of Biology, Bielefeld University, 33615, Bielefeld, Germany
| | - Tony Heitkam
- Faculty of Biology, Institute of Botany, Technische Universität Dresden, 01069, Dresden, Germany.
| | - Daniela Holtgräwe
- Genetics and Genomics of Plants, Center for Biotechnology (CeBiTec) & Faculty of Biology, Bielefeld University, 33615, Bielefeld, Germany.
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5
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Oren A, Garrity GM. Candidatus List No. 2. Lists of names of prokaryotic Candidatus taxa. Int J Syst Evol Microbiol 2021; 71. [PMID: 33881984 DOI: 10.1099/ijsem.0.004671] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- Aharon Oren
- The Institute of Life Sciences, The Hebrew University of Jerusalem, The Edmond J. Safra Campus, 9190401 Jerusalem, Israel
| | - George M Garrity
- Department of Microbiology & Molecular Genetics, Biomedical Physical Sciences, Michigan State University, East Lansing, MI 48824-4320, USA
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6
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Nguyen DT, Wu B, Long H, Zhang N, Patterson C, Simpson S, Morris K, Thomas WK, Lynch M, Hao W. Variable Spontaneous Mutation and Loss of Heterozygosity among Heterozygous Genomes in Yeast. Mol Biol Evol 2021; 37:3118-3130. [PMID: 33219379 DOI: 10.1093/molbev/msaa150] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Mutation and recombination are the primary sources of genetic variation. To better understand the evolution of genetic variation, it is crucial to comprehensively investigate the processes involving mutation accumulation and recombination. In this study, we performed mutation accumulation experiments on four heterozygous diploid yeast species in the Saccharomycodaceae family to determine spontaneous mutation rates, mutation spectra, and losses of heterozygosity (LOH). We observed substantial variation in mutation rates and mutation spectra. We also observed high LOH rates (1.65-11.07×10-6 events per heterozygous site per cell division). Biases in spontaneous mutation and LOH together with selection ultimately shape the variable genome-wide nucleotide landscape in yeast species.
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Affiliation(s)
- Duong T Nguyen
- Department of Biological Sciences, Wayne State University, Detroit, MI
| | - Baojun Wu
- Department of Biological Sciences, Wayne State University, Detroit, MI
| | - Hongan Long
- Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, Shandong Province, China
| | - Nan Zhang
- Department of Biological Sciences, Wayne State University, Detroit, MI
| | | | | | | | | | - Michael Lynch
- Center for Mechanisms of Evolution, The Biodesign Institute, Arizona State University, Tempe, AZ
| | - Weilong Hao
- Department of Biological Sciences, Wayne State University, Detroit, MI
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Godfroid M, Dagan T, Merker M, Kohl TA, Diel R, Maurer FP, Niemann S, Kupczok A. Insertion and deletion evolution reflects antibiotics selection pressure in a Mycobacterium tuberculosis outbreak. PLoS Pathog 2020; 16:e1008357. [PMID: 32997707 PMCID: PMC7549793 DOI: 10.1371/journal.ppat.1008357] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 10/12/2020] [Accepted: 08/18/2020] [Indexed: 11/18/2022] Open
Abstract
In genome evolution, genetic variants are the source of diversity, which natural selection acts upon. Treatment of human tuberculosis (TB) induces a strong selection pressure for the emergence of antibiotic resistance-conferring variants in the infecting Mycobacterium tuberculosis (MTB) strains. MTB evolution in response to treatment has been intensively studied and mainly attributed to point substitutions. However, the frequency and contribution of insertions and deletions (indels) to MTB genome evolution remains poorly understood. Here, we analyzed a multi-drug resistant MTB outbreak for the presence of high-quality indels and substitutions. We find that indels are significantly enriched in genes conferring antibiotic resistance. Furthermore, we show that indels are inherited during the outbreak and follow a molecular clock with an evolutionary rate of 5.37e-9 indels/site/year, which is 23 times lower than the substitution rate. Inherited indels may co-occur with substitutions in genes along related biological pathways; examples are iron storage and resistance to second-line antibiotics. This suggests that epistatic interactions between indels and substitutions affect antibiotic resistance and compensatory evolution in MTB.
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Affiliation(s)
- Maxime Godfroid
- Institute of General Microbiology, Kiel University, Kiel, Germany
| | - Tal Dagan
- Institute of General Microbiology, Kiel University, Kiel, Germany
| | - Matthias Merker
- Molecular and Experimental Mycobacteriology, Research Center Borstel, Borstel, Germany
- German Center for Infection Research, Partner Site Hamburg-Lübeck-Borstel-Riems, Borstel, Germany
| | - Thomas A. Kohl
- Molecular and Experimental Mycobacteriology, Research Center Borstel, Borstel, Germany
- German Center for Infection Research, Partner Site Hamburg-Lübeck-Borstel-Riems, Borstel, Germany
| | - Roland Diel
- German Center for Infection Research, Partner Site Hamburg-Lübeck-Borstel-Riems, Borstel, Germany
- Institute for Epidemiology, University Medical Hospital Schleswig-Holstein, Kiel, Germany
- Lungenclinic Grosshansdorf, Airway Research Center North (ARCN), Member of the German Center for Lung Research (DZL), Großhansdorf, Germany
| | - Florian P. Maurer
- National and WHO Supranational Reference Center for Mycobacteria, Research Center Borstel, Borstel, Germany
- Institute of Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Stefan Niemann
- Molecular and Experimental Mycobacteriology, Research Center Borstel, Borstel, Germany
- German Center for Infection Research, Partner Site Hamburg-Lübeck-Borstel-Riems, Borstel, Germany
| | - Anne Kupczok
- Institute of General Microbiology, Kiel University, Kiel, Germany
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8
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Bacteriophage-Insensitive Mutants of Antimicrobial-Resistant Salmonella Enterica are Altered in their Tetracycline Resistance and Virulence in Caco-2 Intestinal Cells. Int J Mol Sci 2020; 21:ijms21051883. [PMID: 32164202 PMCID: PMC7084636 DOI: 10.3390/ijms21051883] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 02/26/2020] [Accepted: 03/06/2020] [Indexed: 01/21/2023] Open
Abstract
Bacteriophages have shown promise as therapeutic alternatives to antibiotics for the control of infectious bacteria, including the human pathogen Salmonella. However, the development of effective phage-based applications requires the elucidation of key interactions between phages and target hosts, particularly since host resistance to phage is inevitable. Little is known about the alteration of host phenotypes following the development of resistance to phage. The aim of this study is to evaluate the antibiotic susceptibility and virulence of a Salmonella isolate following the development of resistance to bacteriophage SI1. We observed enhanced susceptibility to tetracycline and decreased invasion capacity in a differentiated Caco-2 intestinal cell line. Whole genome sequence analysis revealed an array of mutations, most notably, truncations in vgrG1_2, a core gene involved in Type VI secretion and mutations in the lipopolysaccharide, thereby indicating the plausible attachment site of phage SI1. These findings shed light on understanding the underlying mechanism for phage immunity within the host. Importantly, we reveal an associated genetic cost to the bacterial host with developing resistance to phages. Taken together, these results will aid in advancing strategies to delay or eliminate the development of host resistance when designing informed phage-based antimicrobials.
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9
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Du Y, Song X, Yu H, Lu Z. Complete mitochondrial genome sequence of Tapinoma melanocephalum (Hymenoptera: Formicidae). Mitochondrial DNA B Resour 2019; 4:3448-3449. [PMID: 33366033 PMCID: PMC7707363 DOI: 10.1080/23802359.2019.1674205] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 09/23/2019] [Indexed: 11/12/2022] Open
Abstract
Tapinoma melanocephalum is a ubiquitous invasive species and widely distributed in subtropical and tropical regions around the world. Here, we sequenced and annotated the complete mitochondrial genome (mitogenome) of T. melanocephalum. This mitogenome was 15,499 bp long and encoded 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), and 2 ribosomal RNA unit genes (rRNAs). Compared to other Formicidae species, gene order of T. melanocephalum was not conserved and one tRNA cluster trnW-trnC-trnY converted to trnW-trnY-trnC. The whole mitogenome exhibited heavy AT nucleotide bias (79.5%). All PCGs started with the standard ATN codons. Except for cox1 and nad5 end with the incomplete codon T-, all PCGs terminated with the stop codon TAA. Phylogenetic analysis showed that T. melanocephalum got together with three same subfamily Dolichoderinae species and one Dorylinae species, indicating the close relationship of Dolichoderinae and Dorylinae.
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Affiliation(s)
- Yimin Du
- School of Life Sciences, Gannan Normal University, Ganzhou, Jiangxi, China
- National Navel Orange Engineering and Technology Research Center, Ganzhou, Jiangxi, China
| | - Xiang Song
- School of Life Sciences, Gannan Normal University, Ganzhou, Jiangxi, China
- National Navel Orange Engineering and Technology Research Center, Ganzhou, Jiangxi, China
| | - Haizhong Yu
- School of Life Sciences, Gannan Normal University, Ganzhou, Jiangxi, China
- National Navel Orange Engineering and Technology Research Center, Ganzhou, Jiangxi, China
| | - Zhanjun Lu
- School of Life Sciences, Gannan Normal University, Ganzhou, Jiangxi, China
- National Navel Orange Engineering and Technology Research Center, Ganzhou, Jiangxi, China
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10
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Higuera A, Ramírez JD. Molecular epidemiology of dengue, yellow fever, Zika and Chikungunya arboviruses: An update. Acta Trop 2019; 190:99-111. [PMID: 30444971 DOI: 10.1016/j.actatropica.2018.11.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 11/10/2018] [Accepted: 11/10/2018] [Indexed: 02/06/2023]
Abstract
Arboviruses are a group of viruses transmitted by arthropods. They are characterized by a wide geographic distribution, which is associated with the presence of the vector, and cause asymptomatic infections or febrile diseases in humans in both enzootic and urban cycles. Recent reports of human infections caused by viruses such as dengue, Zika, and chikungunya have raised concern regarding public health, and have led to the re-evaluation of surveillance mechanisms and measures to control the transmission of these arboviruses. Viruses such as Mayaro and Usutu are not currently responsible for a high number of symptomatic infections in humans, but should remain under epidemiological surveillance to avoid the emergence of new epidemics, as happened with Zika virus, that are associated with new or more severe symptoms. Additionally, significant variation has been observed in these viruses, giving rise to different lineages. Until recently, the emergence of new lineages has primarily been related to geographical distribution and dispersion, allowing us to ascertain the possible origins and direction of expansion of each virus type, and to make predictions regarding regions where active infections in humans are likely to occur. Therefore, this review is focused on untangling the molecular epidemiology of Dengue, Yellow fever, Zika and Chikungunya due to their recent epidemics in Latinamerica but provides an update on the geographical distribution globally of these viral variants, and outlines the need for further understanding of the genotypes/lineages assignment.
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11
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Danneels B, Pinto-Carbó M, Carlier A. Patterns of Nucleotide Deletion and Insertion Inferred from Bacterial Pseudogenes. Genome Biol Evol 2018; 10:1792-1802. [PMID: 29982456 PMCID: PMC6054270 DOI: 10.1093/gbe/evy140] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/29/2018] [Indexed: 02/06/2023] Open
Abstract
Pseudogenes are a paradigm of neutral evolution and their study has the potential to reveal intrinsic mutational biases. However, this potential is mitigated by the fact that pseudogenes are quickly purged from bacterial genomes. Here, we assembled a large set of pseudogenes from genomes experiencing reductive evolution as well as functional references for which we could establish reliable phylogenetic relationships. Using this unique dataset, we identified 857 independent insertion and deletion mutations and discover a pervasive bias towards deletions, but not insertions, with sizes multiples of 3 nt. We further show that selective constraints for the preservation of gene frame are unlikely to account for the observed mutational bias and propose that a mechanistic bias in alternative end-joining repair, a recombination-independent double strand break DNA repair mechanism, is responsible for the accumulation of 3n deletions.
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Affiliation(s)
- Bram Danneels
- Department of Biochemistry and Microbiology, Ghent University, Belgium
| | - Marta Pinto-Carbó
- Department of Plant and Microbial Biology, University of Zurich, Switzerland
| | - Aurelien Carlier
- Department of Biochemistry and Microbiology, Ghent University, Belgium
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12
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Santos LA, Adhikarla H, Yan X, Wang Z, Fouts DE, Vinetz JM, Alcantara LCJ, Hartskeerl RA, Goris MGA, Picardeau M, Reis MG, Townsend JP, Zhao H, Ko AI, Wunder EA. Genomic Comparison Among Global Isolates of L. interrogans Serovars Copenhageni and Icterohaemorrhagiae Identified Natural Genetic Variation Caused by an Indel. Front Cell Infect Microbiol 2018; 8:193. [PMID: 29971217 PMCID: PMC6018220 DOI: 10.3389/fcimb.2018.00193] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 05/22/2018] [Indexed: 12/30/2022] Open
Abstract
Leptospirosis is a worldwide zoonosis, responsible for more than 1 million cases and 60,000 deaths every year. Among the 13 pathogenic species of the genus Leptospira, serovars belonging to L. interrogans serogroup Icterohaemorrhagiae are considered to be the most virulent strains, and responsible for majority of the reported severe cases. Serovars Copenhageni and Icterohaemorrhagiae are major representatives of this serogroup and despite their public health relevance, little is known regarding the genetic differences between these two serovars. In this study, we analyzed the genome sequences of 67 isolates belonging to L. interrogans serovars Copenhageni and Icterohaemorrhagiae to investigate the influence of spatial and temporal variations on DNA sequence diversity. Out of the 1072 SNPs identified, 276 were in non-coding regions and 796 in coding regions. Indel analyses identified 258 indels, out of which 191 were found in coding regions and 67 in non-coding regions. Our phylogenetic analyses based on SNP dataset revealed that both serovars are closely related but showed distinct spatial clustering. However, likelihood ratio test of the indel data statistically confirmed the presence of a frameshift mutation within a homopolymeric tract of lic12008 gene (related to LPS biosynthesis) in all the L. interrogans serovar Icterohaemorrhagiae strains but not in the Copenhageni strains. Therefore, this internal indel identified can genetically distinguish L. interrogans serovar Copenhageni from serovar Icterohaemorrhagiae with high discriminatory power. To our knowledge, this is the first study to identify global sequence variations (SNPs and Indels) in L. interrogans serovars Copenhageni and Icterohaemorrhagiae.
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Affiliation(s)
- Luciane A Santos
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States.,Gonçalo Moniz Institute, Oswaldo Cruz Foundation, Salvador, Brazil
| | - Haritha Adhikarla
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States
| | - Xiting Yan
- Department of Biostatistics, Yale School of Public Health, New Haven, CT, United States
| | - Zheng Wang
- Department of Biostatistics, Yale School of Public Health, New Haven, CT, United States
| | | | - Joseph M Vinetz
- Division of Infectious Diseases, Department of Medicine, University of California San Diego School of Medicine, La Jolla, CA, United States
| | | | - Rudy A Hartskeerl
- Royal Tropical Institute, KIT Biomedical Research, Amsterdam, Netherlands
| | - Marga G A Goris
- Royal Tropical Institute, KIT Biomedical Research, Amsterdam, Netherlands
| | | | | | - Jeffrey P Townsend
- Department of Biostatistics, Yale School of Public Health, New Haven, CT, United States
| | - Hongyu Zhao
- Department of Biostatistics, Yale School of Public Health, New Haven, CT, United States
| | - Albert I Ko
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States.,Gonçalo Moniz Institute, Oswaldo Cruz Foundation, Salvador, Brazil
| | - Elsio A Wunder
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States.,Gonçalo Moniz Institute, Oswaldo Cruz Foundation, Salvador, Brazil
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13
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Ahrens JB, Nunez-Castilla J, Siltberg-Liberles J. Evolution of intrinsic disorder in eukaryotic proteins. Cell Mol Life Sci 2017; 74:3163-3174. [PMID: 28597295 PMCID: PMC11107722 DOI: 10.1007/s00018-017-2559-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 06/01/2017] [Indexed: 12/23/2022]
Abstract
Conformational flexibility conferred though regions of intrinsic structural disorder allows proteins to behave as dynamic molecules. While it is well-known that intrinsically disordered regions can undergo disorder-to-order transitions in real-time as part of their function, we also are beginning to learn more about the dynamics of disorder-to-order transitions along evolutionary time-scales. Intrinsically disordered regions endow proteins with functional promiscuity, which is further enhanced by the ability of some of these regions to undergo real-time disorder-to-order transitions. Disorder content affects gene retention after whole genome duplication, but it is not necessarily conserved. Altered patterns of disorder resulting from evolutionary disorder-to-order transitions indicate that disorder evolves to modify function through refining stability, regulation, and interactions. Here, we review the evolution of intrinsically disordered regions in eukaryotic proteins. We discuss the interplay between secondary structure and disorder on evolutionary time-scales, the importance of disorder for eukaryotic proteome expansion and functional divergence, and the evolutionary dynamics of disorder.
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Affiliation(s)
- Joseph B Ahrens
- Department of Biological Sciences, Biomolecular Sciences Institute, Florida International University, 11200 SW 8th St, Miami, FL, 33199, USA
| | - Janelle Nunez-Castilla
- Department of Biological Sciences, Biomolecular Sciences Institute, Florida International University, 11200 SW 8th St, Miami, FL, 33199, USA
| | - Jessica Siltberg-Liberles
- Department of Biological Sciences, Biomolecular Sciences Institute, Florida International University, 11200 SW 8th St, Miami, FL, 33199, USA.
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Wernegreen JJ. Ancient bacterial endosymbionts of insects: Genomes as sources of insight and springboards for inquiry. Exp Cell Res 2017; 358:427-432. [DOI: 10.1016/j.yexcr.2017.04.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 04/24/2017] [Accepted: 04/25/2017] [Indexed: 01/20/2023]
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Abstract
BACKGROUND Despite the long-anticipated possibility of putting sequence alignment on the same footing as statistical phylogenetics, theorists have struggled to develop time-dependent evolutionary models for indels that are as tractable as the analogous models for substitution events. MAIN TEXT This paper discusses progress in the area of insertion-deletion models, in view of recent work by Ezawa (BMC Bioinformatics 17:304, 2016); (BMC Bioinformatics 17:397, 2016); (BMC Bioinformatics 17:457, 2016) on the calculation of time-dependent gap length distributions in pairwise alignments, and current approaches for extending these approaches from ancestor-descendant pairs to phylogenetic trees. CONCLUSIONS While approximations that use finite-state machines (Pair HMMs and transducers) currently represent the most practical approach to problems such as sequence alignment and phylogeny, more rigorous approaches that work directly with the matrix exponential of the underlying continuous-time Markov chain also show promise, especially in view of recent advances.
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Affiliation(s)
- Ian H. Holmes
- 0000 0001 2181 7878grid.47840.3fDept of Bioengineering, University of California, Berkeley, 94720 USA
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Zhao H, He S, Zhu Y, Cao X, Luo R, Cai Y, Xu H, Sun X. A novel 29 bp insertion/deletion (indel) variant of the <i>LHX3</i> gene and its influence on growth traits in four sheep breeds of various fecundity. Arch Anim Breed 2017. [DOI: 10.5194/aab-60-79-2017] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Abstract. Belonging to the same LIM homeobox (LHX) family, LHX3 and LHX4 are key transcription factors in animal growth and reproduction. Insertion/deletion (indel) is a relatively simple and effective DNA marker. Therefore, four sheep breeds of various fecundity were used to explore the novel indel variants within the sheep LHX3 and LHX4 gene, as well as to evaluate their effects on growth traits. Herein, only one novel 29 bp indel (NC_019460.2:g.3107494-3107522delGGCCTGGACTGTGATGGGCACCCTCCGGG) within the sheep LHX3 gene was found, and three genotypes were detected. Interestingly, the increasing trends of II (insertion/insertion) genotype frequency and I allelic frequency were the same as the growth of the fertility character. Genotypic frequency and allelic frequency distributions were significantly different between the high-fecundity breeds (HS, STHS and LFTS) and low-fecundity breed (TS) based on a χ2 test (P < 0.05). Association analyses showed that body length was significantly different in female TS and STHS and that chest width was significantly different for the female TS and male STHS (P < 0.05). These findings suggested that the 29 bp indel could extend the spectrum of genetic variations of the LHX3 gene in sheep and provide a valuable theoretical basis for the marker-assisted selection (MAS) in sheep breeding and genetics.
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Chen PY, Zheng BY, Liu JX, Wei SJ. Next-Generation Sequencing of Two Mitochondrial Genomes from Family Pompilidae (Hymenoptera: Vespoidea) Reveal Novel Patterns of Gene Arrangement. Int J Mol Sci 2016; 17:ijms17101641. [PMID: 27727175 PMCID: PMC5085674 DOI: 10.3390/ijms17101641] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2016] [Revised: 09/14/2016] [Accepted: 09/20/2016] [Indexed: 01/09/2023] Open
Abstract
Animal mitochondrial genomes have provided large and diverse datasets for evolutionary studies. Here, the first two representative mitochondrial genomes from the family Pompilidae (Hymenoptera: Vespoidea) were determined using next-generation sequencing. The sequenced region of these two mitochondrial genomes from the species Auplopus sp. and Agenioideus sp. was 16,746 bp long with an A + T content of 83.12% and 16,596 bp long with an A + T content of 78.64%, respectively. In both species, all of the 37 typical mitochondrial genes were determined. The secondary structure of tRNA genes and rRNA genes were predicted and compared with those of other insects. Atypical trnS1 using abnormal anticodons TCT and lacking D-stem pairings was identified. There were 49 helices belonging to six domains in rrnL and 30 helices belonging to three domains in rrns present. Compared with the ancestral organization, four and two tRNA genes were rearranged in mitochondrial genomes of Auplopus and Agenioideus, respectively. In both species, trnM was shuffled upstream of the trnI-trnQ-trnM cluster, and trnA was translocated from the cluster trnA-trnR-trnN-trnS1-trnE-trnF to the region between nad1 and trnL1, which is novel to the Vespoidea. In Auplopus, the tRNA cluster trnW-trnC-trnY was shuffled to trnW-trnY-trnC. Phylogenetic analysis within Vespoidea revealed that Pompilidae and Mutillidae formed a sister lineage, and then sistered Formicidae. The genomes presented in this study have enriched the knowledge base of molecular markers, which is valuable in respect to studies about the gene rearrangement mechanism, genomic evolutionary processes and phylogeny of Hymenoptera.
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Affiliation(s)
- Peng-Yan Chen
- Institute of Plant and Environmental Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China.
- Department of Entomology, South China Agricultural University, Guangzhou 510640, China.
| | - Bo-Ying Zheng
- Institute of Plant and Environmental Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China.
| | - Jing-Xian Liu
- Department of Entomology, South China Agricultural University, Guangzhou 510640, China.
| | - Shu-Jun Wei
- Institute of Plant and Environmental Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China.
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18
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The pioneering role of PRDM9 indel mutations in tarsier evolution. Sci Rep 2016; 6:34618. [PMID: 27698394 PMCID: PMC5048142 DOI: 10.1038/srep34618] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 09/09/2016] [Indexed: 01/01/2023] Open
Abstract
PRDM9 is currently the sole speciation gene found in vertebrates causing hybrid sterility probably due to incompatible alleles. Its role in defining the double strand break loci during the meiotic prophase I is crucial for proper chromosome segregation. Therefore, the rapid turnover of the loci determining zinc finger array seems to be causative for incompatibilities. We here investigated the zinc finger domain-containing exon of PRDM9 in 23 tarsiers. Tarsiers, the most basal extant haplorhine primates, exhibit two frameshifting indels at the 5'-end of the array. The first mutation event interrupts the reading frame and function while the second compensates both. The fixation of this allele variant in tarsiers led to hypothesize that de- and reactivation of the zinc finger domain drove the speciation in early haplorhine or tarsiiform primates. Moreover, the high allelic diversity within Tarsius points to multiple effects of genetic drift reflecting their phylogeographic history since the Miocene.
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Clayton AL, Jackson DG, Weiss RB, Dale C. Adaptation by Deletogenic Replication Slippage in a Nascent Symbiont. Mol Biol Evol 2016; 33:1957-66. [PMID: 27189544 PMCID: PMC4948707 DOI: 10.1093/molbev/msw071] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
As a consequence of population level constraints in the obligate, host-associated lifestyle, intracellular symbiotic bacteria typically exhibit high rates of molecular sequence evolution and extensive genome degeneration over the course of their host association. While the rationale for genome degeneration is well understood, little is known about the molecular mechanisms driving this change. To understand these mechanisms we compared the genome of Sodalis praecaptivus, a nonhost associated bacterium that is closely related to members of the Sodalis-allied clade of insect endosymbionts, with the very recently derived insect symbiont Candidatus Sodalis pierantonius. The characterization of indel mutations in the genome of Ca. Sodalis pierantonius shows that the replication system in this organism is highly prone to deletions resulting from polymerase slippage events in regions encoding G+C-rich repetitive sequences. This slippage-prone phenotype is mechanistically associated with the loss of certain components of the bacterial DNA recombination machinery at an early stage in symbiotic life and is expected to facilitate rapid adaptation to the novel host environment. This is analogous to the emergence of mutator strains in both natural and laboratory populations of bacteria, which tend to reach high frequencies in clonal populations due to linkage between the mutator allele and the resulting adaptive mutations.
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Affiliation(s)
| | | | | | - Colin Dale
- Department of Biology, University of Utah
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20
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Thiyagarajan K, Vitali F, Tolaini V, Galeffi P, Cantale C, Vikram P, Singh S, De Rossi P, Nobili C, Procacci S, Del Fiore A, Antonini A, Presenti O, Brunori A. Genomic Characterization of Phenylalanine Ammonia Lyase Gene in Buckwheat. PLoS One 2016; 11:e0151187. [PMID: 26990297 PMCID: PMC4798664 DOI: 10.1371/journal.pone.0151187] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 02/24/2016] [Indexed: 01/05/2023] Open
Abstract
Phenylalanine Ammonia Lyase (PAL) gene which plays a key role in bio-synthesis of medicinally important compounds, Rutin/quercetin was sequence characterized for its efficient genomics application. These compounds possessing anti-diabetic and anti-cancer properties and are predominantly produced by Fagopyrum spp. In the present study, PAL gene was sequenced from three Fagopyrum spp. (F. tataricum, F. esculentum and F. dibotrys) and showed the presence of three SNPs and four insertion/deletions at intra and inter specific level. Among them, the potential SNP (position 949th bp G>C) with Parsimony Informative Site was selected and successfully utilised to individuate the zygosity/allelic variation of 16 F. tataricum varieties. Insertion mutations were identified in coding region, which resulted the change of a stretch of 39 amino acids on the putative protein. Our Study revealed that autogamous species (F. tataricum) has lower frequency of observed SNPs as compared to allogamous species (F. dibotrys and F. esculentum). The identified SNPs in F. tataricum didn't result to amino acid change, while in other two species it caused both conservative and non-conservative variations. Consistent pattern of SNPs across the species revealed their phylogenetic importance. We found two groups of F. tataricum and one of them was closely related with F. dibotrys. Sequence characterization information of PAL gene reported in present investigation can be utilized in genetic improvement of buckwheat in reference to its medicinal value.
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Affiliation(s)
- Karthikeyan Thiyagarajan
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), UTAGRI- INN, Via Anguillarese, 301, 00123 Rome, Italy
- Bioversity International, 00054, Maccarese (Fiumicino), Italy
| | - Fabio Vitali
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), UTAGRI- INN, Via Anguillarese, 301, 00123 Rome, Italy
| | - Valentina Tolaini
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), UTAGRI- INN, Via Anguillarese, 301, 00123 Rome, Italy
| | - Patrizia Galeffi
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), UTAGRI- INN, Via Anguillarese, 301, 00123 Rome, Italy
| | - Cristina Cantale
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), UTAGRI- INN, Via Anguillarese, 301, 00123 Rome, Italy
| | - Prashant Vikram
- Genetic Resource Program, International Center for Maize and Wheat Improvement, El Batan, Texcoco, Mexico
| | - Sukhwinder Singh
- Genetic Resource Program, International Center for Maize and Wheat Improvement, El Batan, Texcoco, Mexico
| | - Patrizia De Rossi
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), UTAGRI- INN, Via Anguillarese, 301, 00123 Rome, Italy
| | - Chiara Nobili
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), UTAGRI- INN, Via Anguillarese, 301, 00123 Rome, Italy
| | - Silvia Procacci
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), UTAGRI- INN, Via Anguillarese, 301, 00123 Rome, Italy
| | - Antonella Del Fiore
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), UTAGRI- INN, Via Anguillarese, 301, 00123 Rome, Italy
| | - Alessandro Antonini
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), UTAGRI- INN, Via Anguillarese, 301, 00123 Rome, Italy
| | - Ombretta Presenti
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), UTAGRI- INN, Via Anguillarese, 301, 00123 Rome, Italy
| | - Andrea Brunori
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), UTAGRI- INN, Via Anguillarese, 301, 00123 Rome, Italy
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21
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Vaksman Z, Garner HR. Somatic microsatellite variability as a predictive marker for colorectal cancer and liver cancer progression. Oncotarget 2016; 6:5760-71. [PMID: 25691061 PMCID: PMC4467400 DOI: 10.18632/oncotarget.3306] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 01/02/2015] [Indexed: 12/13/2022] Open
Abstract
Microsatellites (MSTs) are short tandem repeated genetic motifs that comprise ~3% of the genome. MST instability (MSI), defined as acquired/lost primary alleles at a small subset of microsatellite loci (e.g. Bethesda markers), is a clinically relevant marker for colorectal cancer. However, these markers are not applicable to other types of cancers, specifically, for liver cancer which has a high mortality rate. Here we show that somatic MST variability (SMV), defined as the presence of additional, non-primary (aka minor) alleles at MST loci, is a complementary measure of MSI, and a genetic marker for colorectal and liver cancer. Re-analysis of Illumina sequenced exomes from The Cancer Genome Atlas indicates that SMV may distinguish a subpopulation of African American patients with colorectal cancer, which represents ~33% of the population in this study. Further, for liver cancer, a higher rate of SMV may be indicative of an earlier age of onset. The work presented here suggests that classical MSI should be expanded to include SMV, going beyond alterations of the primary alleles at a small number of microsatellite loci. This measure of SMV may represent a potential new diagnostic for a variety of cancers and may provide new information for colorectal cancer patients.
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Affiliation(s)
- Zalman Vaksman
- Virginia Bioinformatics Institute, Virginia Tech, Blacksburg, VA, USA
| | - Harold R Garner
- Virginia Bioinformatics Institute, Virginia Tech, Blacksburg, VA, USA
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22
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Kim MJ, Hong EJ, Kim I. Complete mitochondrial genome of Camponotus atrox (Hymenoptera: Formicidae): a new tRNA arrangement in Hymenoptera. Genome 2016; 59:59-74. [DOI: 10.1139/gen-2015-0080] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We sequenced the complete mitochondrial (mt) genome of Camponotus atrox (Hymenoptera: Formicidae), which is only distributed in Korea. The genome was 16 540 bp in size and contained typical sets of genes (13 protein-coding genes, 22 tRNAs, and 2 rRNAs). The C. atrox A+T-rich region, at 1402 bp, was the longest of all sequenced ant genomes and was composed of an identical tandem repeat consisting of six 100-bp copies and one 96-bp copy. A total of 315 bp of intergenic spacer sequence was spread over 23 regions. An alignment of the spacer sequences in ants was largely feasible among congeneric species, and there was substantial sequence divergence, indicating their potential use as molecular markers for congeneric species. The A/T contents at the first and second codon positions of protein-coding genes (PCGs) were similar for ant species, including C. atrox (73.9% vs. 72.3%, on average). With increased taxon sampling among hymenopteran superfamilies, differences in the divergence rates (i.e., the non-synonymous substitution rates) between the suborders Symphyta and Apocrita were detected, consistent with previous results. The C. atrox mt genome had a unique gene arrangement, trnI-trnM-trnQ, at the A+T-rich region and ND2 junction (underline indicates inverted gene). This may have originated from a tandem duplication of trnM-trnI, resulting in trnM-trnI-trnM-trnI-trnQ, and the subsequent loss of the first trnM and second trnI, resulting in trnI-trnM-trnQ.
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Affiliation(s)
- Min Jee Kim
- College of Agriculture & Life Sciences, Chonnam National University, Gwangju 500-757, Republic of Korea
| | - Eui Jeong Hong
- National Park Research Institute, Korea National Park Service, Wonju, Gangwon-do 570-811, Republic of Korea
| | - Iksoo Kim
- College of Agriculture & Life Sciences, Chonnam National University, Gwangju 500-757, Republic of Korea
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23
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Paul RA, Rudramurthy SM, Meis JF, Mouton JW, Chakrabarti A. A Novel Y319H Substitution in CYP51C Associated with Azole Resistance in Aspergillus flavus. Antimicrob Agents Chemother 2015; 59:6615-9. [PMID: 26248359 PMCID: PMC4576050 DOI: 10.1128/aac.00637-15] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 07/10/2015] [Indexed: 11/20/2022] Open
Abstract
This study aimed to explore any mutation in the CYP51 gene conferring azole resistance in Aspergillus flavus. Two voriconazole-resistant and 45 voriconazole-susceptible isolates were included in the study. Sequence analysis demonstrated a T1025C nucleotide change in CYP51C, resulting in the Y319H amino acid substitution in one resistant isolate. However, the earlier described T788G mutation in CYP51C conferring voriconazole resistance in A. flavus isolates was present in all isolates, irrespective of their susceptibility status.
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Affiliation(s)
- R A Paul
- Department of Medical Microbiology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - S M Rudramurthy
- Department of Medical Microbiology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - J F Meis
- Department of Medical Microbiology and Infectious Diseases, Canisius Wilhelmina Hospital, Nijmegen, The Netherlands Department of Medical Microbiology and Infectious Diseases, Erasmus MC, Rotterdam, The Netherlands
| | - J W Mouton
- Department of Medical Microbiology and Infectious Diseases, Canisius Wilhelmina Hospital, Nijmegen, The Netherlands Department of Medical Microbiology and Infectious Diseases, Erasmus MC, Rotterdam, The Netherlands
| | - A Chakrabarti
- Department of Medical Microbiology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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24
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Abstract
Background Many genetic variants have been identified in the human genome. The functional effects of a single variant have been intensively studied. However, the joint effects of multiple variants in the same genes have been largely ignored due to their complexity or lack of data. This paper uses HMMvar, a hidden Markov model based approach, to investigate the combined effect of multiple variants from the 1000 Genomes Project. Two tumor suppressor genes, TP53 and phosphatase and tensin homolog (PTEN), are also studied for the joint effect of compensatory indel variants. Results Results show that there are cases where the joint effect of having multiple variants in the same genes is significantly different from that of a single variant. The deleterious effect of a single indel variant can be alleviated by their compensatory indels in TP53 and PTEN. Compound mutations in two genes, β-MHC and MyBP-C, leading to severer cardiovascular disease compared to single mutations, are also validated. Conclusions This paper extends the functionality of HMMvar, a tool for assigning a quantitative score to a variant, to measure not only the deleterious effect of a single variant but also the joint effect of multiple variants. HMMvar is the first tool that can predict the functional effects of both single and general multiple variations on proteins. The precomputed scores for multiple variants from the 1000 Genomes Project and the HMMvar package are available at https://bioinformatics.cs.vt.edu/zhanglab/HMMvar/
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Affiliation(s)
- Mingming Liu
- Department of Computer Science, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
| | - Layne T Watson
- Department of Computer Science, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA. .,Department of Mathematics, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA. .,Department of Aerospace and Ocean Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
| | - Liqing Zhang
- Department of Computer Science, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
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25
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Williams LE, Wernegreen JJ. Genome evolution in an ancient bacteria-ant symbiosis: parallel gene loss among Blochmannia spanning the origin of the ant tribe Camponotini. PeerJ 2015; 3:e881. [PMID: 25861561 PMCID: PMC4389277 DOI: 10.7717/peerj.881] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 03/18/2015] [Indexed: 12/11/2022] Open
Abstract
Stable associations between bacterial endosymbionts and insect hosts provide opportunities to explore genome evolution in the context of established mutualisms and assess the roles of selection and genetic drift across host lineages and habitats. Blochmannia, obligate endosymbionts of ants of the tribe Camponotini, have coevolved with their ant hosts for ∼40 MY. To investigate early events in Blochmannia genome evolution across this ant host tribe, we sequenced Blochmannia from two divergent host lineages, Colobopsis obliquus and Polyrhachis turneri, and compared them with four published genomes from Blochmannia of Camponotus sensu stricto. Reconstructed gene content of the last common ancestor (LCA) of these six Blochmannia genomes is reduced (690 protein coding genes), consistent with rapid gene loss soon after establishment of the symbiosis. Differential gene loss among Blochmannia lineages has affected cellular functions and metabolic pathways, including DNA replication and repair, vitamin biosynthesis and membrane proteins. Blochmannia of P. turneri (i.e., B. turneri) encodes an intact DnaA chromosomal replication initiation protein, demonstrating that loss of dnaA was not essential for establishment of the symbiosis. Based on gene content, B. obliquus and B. turneri are unable to provision hosts with riboflavin. Of the six sequenced Blochmannia, B. obliquus is the earliest diverging lineage (i.e., the sister group of other Blochmannia sampled) and encodes the fewest protein-coding genes and the most pseudogenes. We identified 55 genes involved in parallel gene loss, including glutamine synthetase, which may participate in nitrogen recycling. Pathways for biosynthesis of coenzyme A, terpenoids and riboflavin were lost in multiple lineages, suggesting relaxed selection on the pathway after inactivation of one component. Analysis of Illumina read datasets did not detect evidence of plasmids encoding missing functions, nor the presence of coresident symbionts other than Wolbachia. Although gene order is strictly conserved in four Blochmannia of Camponotus sensu stricto, comparisons with deeply divergent lineages revealed inversions in eight genomic regions, indicating ongoing recombination despite ancestral loss of recA. In sum, the addition of two Blochmannia genomes of divergent host lineages enables reconstruction of early events in evolution of this symbiosis and suggests that Blochmannia lineages may experience distinct, host-associated selective pressures. Understanding how evolutionary forces shape genome reduction in this system may help to clarify forces driving gene loss in other bacteria, including intracellular pathogens.
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Affiliation(s)
- Laura E Williams
- Duke Center for Genomic and Computational Biology, Duke University , Durham, NC , USA
| | - Jennifer J Wernegreen
- Duke Center for Genomic and Computational Biology, Duke University , Durham, NC , USA ; Nicholas School of the Environment, Duke University , Durham, NC , USA
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26
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Santos-Garcia D, Vargas-Chavez C, Moya A, Latorre A, Silva FJ. Genome evolution in the primary endosymbiont of whiteflies sheds light on their divergence. Genome Biol Evol 2015; 7:873-88. [PMID: 25716826 PMCID: PMC5322561 DOI: 10.1093/gbe/evv038] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Whiteflies are important agricultural insect pests, whose evolutionary success is related to a long-term association with a bacterial endosymbiont, Candidatus Portiera aleyrodidarum. To completely characterize this endosymbiont clade, we sequenced the genomes of three new Portiera strains covering the two extant whitefly subfamilies. Using endosymbiont and mitochondrial sequences we estimated the divergence dates in the clade and used these values to understand the molecular evolution of the endosymbiont coding sequences. Portiera genomes were maintained almost completely stable in gene order and gene content during more than 125 Myr of evolution, except in the Bemisia tabaci lineage. The ancestor had already lost the genetic information transfer autonomy but was able to participate in the synthesis of all essential amino acids and carotenoids. The time of divergence of the B. tabaci complex was much more recent than previous estimations. The recent divergence of biotypes B (MEAM1 species) and Q (MED species) suggests that they still could be considered strains of the same species. We have estimated the rates of evolution of Portiera genes, synonymous and nonsynonymous, and have detected significant differences among-lineages, with most Portiera lineages evolving very slowly. Although the nonsynonymous rates were much smaller than the synonymous, the genomic dN/dS ratios were similar, discarding selection as the driver of among-lineage variation. We suggest variation in mutation rate and generation time as the responsible factors. In conclusion, the slow evolutionary rates of Portiera may have contributed to its long-term association with whiteflies, avoiding its replacement by a novel and more efficient endosymbiont.
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Affiliation(s)
- Diego Santos-Garcia
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, Spain
| | - Carlos Vargas-Chavez
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, Spain
| | - Andrés Moya
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, Spain Unidad Mixta de Investigación en Genómica y Salud, FISABIO-Salud Pública and Universitat de València, Spain
| | - Amparo Latorre
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, Spain Unidad Mixta de Investigación en Genómica y Salud, FISABIO-Salud Pública and Universitat de València, Spain
| | - Francisco J Silva
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, Spain Unidad Mixta de Investigación en Genómica y Salud, FISABIO-Salud Pública and Universitat de València, Spain
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Yang S, Li X, Cai LG, Qian ZQ. Characterization of the complete mitochondrial genome of Formica selysi (Insecta: Hymenoptera: Formicidae: Formicinae). Mitochondrial DNA A DNA Mapp Seq Anal 2015; 27:3378-80. [PMID: 25703846 DOI: 10.3109/19401736.2015.1018229] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The complete mitochondrial genome of Formica selysi has been assembled from Illumina sequencing data with an average coverage of 2733X. The circular genome was 16,752 bp in length, and consists of 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), two ribosomal RNAs (rRNAs) and one D-loop region. All PCGs initiated with ATN codons and terminated with the TAA codon. The nucleotide composition was highly asymmetric (40.33% A, 11.07% C, 5.66% G and 42.94% T) with an overall GC content of 16.73%. Unlike those of most other insects, the mitochondrial genome of F. selysi was characterized by an obviously high proportion of intergenic spacers. These data would contribute to the evolutionary studies of this and related ant taxa.
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Affiliation(s)
- Sen Yang
- a College of Life Sciences, Shaanxi Normal University , Xi'an , Shaanxi , P. R. China .,b Department of Physical Education , Xianyang Normal University , Xianyang , Shaanxi , P. R. China , and
| | - Xin Li
- c State Key Laboratory of Plant Cell and Chromosome Engineering , National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences , Beijing , P. R. China
| | - Lei-Gang Cai
- a College of Life Sciences, Shaanxi Normal University , Xi'an , Shaanxi , P. R. China
| | - Zeng-Qiang Qian
- a College of Life Sciences, Shaanxi Normal University , Xi'an , Shaanxi , P. R. China
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28
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Heritable symbiosis: The advantages and perils of an evolutionary rabbit hole. Proc Natl Acad Sci U S A 2015; 112:10169-76. [PMID: 25713367 DOI: 10.1073/pnas.1421388112] [Citation(s) in RCA: 282] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Many eukaryotes have obligate associations with microorganisms that are transmitted directly between generations. A model for heritable symbiosis is the association of aphids, a clade of sap-feeding insects, and Buchnera aphidicola, a gammaproteobacterium that colonized an aphid ancestor 150 million years ago and persists in almost all 5,000 aphid species. Symbiont acquisition enables evolutionary and ecological expansion; aphids are one of many insect groups that would not exist without heritable symbiosis. Receiving less attention are potential negative ramifications of symbiotic alliances. In the short run, symbionts impose metabolic costs. Over evolutionary time, hosts evolve dependence beyond the original benefits of the symbiosis. Symbiotic partners enter into an evolutionary spiral that leads to irreversible codependence and associated risks. Host adaptations to symbiosis (e.g., immune-system modification) may impose vulnerabilities. Symbiont genomes also continuously accumulate deleterious mutations, limiting their beneficial contributions and environmental tolerance. Finally, the fitness interests of obligate heritable symbionts are distinct from those of their hosts, leading to selfish tendencies. Thus, genes underlying the host-symbiont interface are predicted to follow a coevolutionary arms race, as observed for genes governing host-pathogen interactions. On the macroevolutionary scale, the rapid evolution of interacting symbiont and host genes is predicted to accelerate host speciation rates by generating genetic incompatibilities. However, degeneration of symbiont genomes may ultimately limit the ecological range of host species, potentially increasing extinction risk. Recent results for the aphid-Buchnera symbiosis and related systems illustrate that, whereas heritable symbiosis can expand ecological range and spur diversification, it also presents potential perils.
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29
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Civetta A. Adaptive evolution at immune system genes and deep pregnancy implantation in primates. Genomics 2015; 105:17-22. [PMID: 25451741 DOI: 10.1016/j.ygeno.2014.11.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 11/06/2014] [Accepted: 11/07/2014] [Indexed: 12/31/2022]
Abstract
A major evolutionary change in the lineage ancestral to humans, chimpanzee and gorilla (HCG) has been the embedding of the embryo into maternal tissue. Thus, the first layer of cells (trophoblast) to differentiate after fertilization must adapt to invade the uterus. Such event would likely leave signatures of positive selection at genes with roles in embryo implantation. Here, 163 pregnancy implantation genes are tested for evidence of adaptive diversification in the ancestral lineage to HCG. Two immune system genes, HLA-E and KIR2DL4 showed evidence of positive selection. Some of the positive selected sites involve amino acid substitution with predicted damaging effects on protein function, thus highlighting the possibility of antagonistic pleiotropic effects. Selection at a gene coding for a receptor expressed in uterine cells (KIR) that interacts with trophoblast human leukocyte antigen (HLA) genes suggests a main role for immunological adaptations in embryo deep invasion of the maternal endometrium.
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Affiliation(s)
- Alberto Civetta
- Department of Biology, University of Winnipeg, Winnipeg, Manitoba, Canada.
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30
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Mao M, Gibson T, Dowton M. Higher-level phylogeny of the Hymenoptera inferred from mitochondrial genomes. Mol Phylogenet Evol 2014; 84:34-43. [PMID: 25542648 DOI: 10.1016/j.ympev.2014.12.009] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 11/27/2014] [Accepted: 12/16/2014] [Indexed: 11/25/2022]
Abstract
Higher-level hymenopteran relationships remain unresolved in both morphological and molecular analyses. In this study, we present the most comprehensive analyses of hymenopteran relationships based on 48 mitochondrial (mt) genomes. One complete and two nearly complete mt genomes representing three hymenopteran superfamilies were newly sequenced. We assessed the influence of inclusion/exclusion of 3rd codon positions, alignment approaches, partition schemes and phylogenetic approaches on topology and nodal support within the Hymenoptera. The results showed that the topologies were sensitive to the variation of dataset and analytical approach. However, some robust and highly supported relationships were recovered: the Ichneumonomorpha was monophyletic; the Trigonalyoidea+Megalyroidea and the Diaprioidea+Chalcidoidea were consistently recovered; the Cynipoidea was generally recovered as the sister group to the Diaprioidea+Chalcidoidea. In addition, the monophyletic Aculeata and Proctotrupomorpha were recovered in some analyses. Several gene rearrangements were detected in each of the three newly sequenced mt genomes. Specifically, the Ibalia leucospoides mt genome harbors a large inversion of a gene block from trnE to trnS2. Inverted, duplicated A+T rich regions were detected in the Ibalia leucospoides mt genome, which probably played an important role during the formation of the large gene block inversion via recombination.
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Affiliation(s)
- Meng Mao
- Centre for Medical Bioscience, School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia.
| | - Tracey Gibson
- Centre for Medical Bioscience, School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Mark Dowton
- Centre for Medical Bioscience, School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
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31
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Veerappa AM, Vishweswaraiah S, Lingaiah K, Murthy NM, Suresh RV, Belur K, Ramachandra NB, Tejaswini, Patel NB, Gowda PKS. Insertion-deletions burden in copy number polymorphisms of the Tibetan population. INDIAN JOURNAL OF HUMAN GENETICS 2014; 20:166-74. [PMID: 25400346 PMCID: PMC4228569 DOI: 10.4103/0971-6866.142888] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND: Many studies have been conducted to identify either insertions-deletions (inDels) or copy number variations (CNVs) in humans, but few studies have been conducted to identify both of these forms coexisting in the same region. AIMS AND OBJECTIVES: To map the functionally significant sites within human genes that are likely to influence human traits and diseases. MATERIALS AND METHODS: In this report, we describe an inDel map in the 1051 Tibetan CNV regions obtained through CNV genotyping using Affymetrix Genome-wide single nucleotide polymorphism 6.0 chip. InDel polymorphisms in these copy number polymorphism regions were identified with a computational approach using the 2500 deoxyribonucleic acid sequences obtained from the 1000 Genome Project. RESULTS: The study identified a total of 95935 inDels that range from 1 bp to several bps in length which were found scattered across regulatory regions, exons and in introns of genes underlying the CNVs. A study on the distribution of inDels revealed that the majority of inDels were found in coding regions of the genome than the noncoding, while within the genes, inDels in intron regions were more followed by exonic regions and finally the regulatory regions. CONCLUSION: Study of inDels in CNV regions contribute to the enhanced understanding of the role played by the two variations and their collective influence on the genome. Further, a collection of these inDel genetic markers will aid in genetic mapping, further understanding of the phenotypic variability, identification of disease genes and in detecting novel CNVs.
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Affiliation(s)
| | | | - Kusuma Lingaiah
- Department of Neurology, JSS Hospital, Mysore, Karnataka, India
| | - N Megha Murthy
- Department of Neurology, JSS Hospital, Mysore, Karnataka, India
| | | | - Keshava Belur
- Department of Neurology, JSS Hospital, Mysore, Karnataka, India
| | - Nallur B Ramachandra
- Department of Studies in Zoology, University of Mysore, Manasagangotri, Mysore, Karnataka, India
| | - Tejaswini
- Department of Studies in Zoology, University of Mysore, Manasagangotri, Mysore, Karnataka, India
| | - Niveditha B Patel
- Department of Studies in Zoology, University of Mysore, Manasagangotri, Mysore, Karnataka, India
| | - P K Supriya Gowda
- Department of Studies in Zoology, University of Mysore, Manasagangotri, Mysore, Karnataka, India
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32
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Salahuddin P, Khan AU. Studies on structure-based sequence alignment and phylogenies of beta-lactamases. Bioinformation 2014; 10:308-13. [PMID: 24966539 PMCID: PMC4070041 DOI: 10.6026/97320630010308] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 05/21/2014] [Indexed: 11/23/2022] Open
Abstract
The β-lactamases enzymes cleave the amide bond in β-lactam ring, rendering β-lactam antibiotics harmless to bacteria. In this communication we have studied structure-function relationship and phylogenies of class A, B and D beta-lactamases using structure-based sequence alignment and phylip programs respectively. The data of structure-based sequence alignment suggests that in different isolates of TEM-1, mutations did not occur at or near sequence motifs. Since deletions are reported to be lethal to structure and function of enzyme. Therefore, in these variants antibiotic hydrolysis profile and specificity will be affected. The alignment data of class A enzyme SHV-1, CTX-M-15, class D enzyme, OXA-10, and class B enzyme VIM-2 and SIM-1 show sequence motifs along with other part of polypeptide are essentially conserved. These results imply that conformations of betalactamases are close to native state and possess normal hydrolytic activities towards beta-lactam antibiotics. However, class B enzyme such as IMP-1 and NDM-1 are less conserved than other class A and D studied here because mutation and deletions occurred at critically important region such as active site. Therefore, the structure of these beta-lactamases will be altered and antibiotic hydrolysis profile will be affected. Phylogenetic studies suggest that class A and D beta-lactamases including TOHO-1 and OXA-10 respectively evolved by horizontal gene transfer (HGT) whereas other member of class A such as TEM-1 evolved by gene duplication mechanism. Taken together, these studies justify structure-function relationship of beta-lactamases and phylogenetic studies suggest these enzymes evolved by different mechanisms.
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Affiliation(s)
- Parveen Salahuddin
- Distributed Information Sub-Centre, Interdisciplinary Biotechnology Unit, A. M. U. Aligarh, 202002, India
| | - Asad U Khan
- Distributed Information Sub-Centre, Interdisciplinary Biotechnology Unit, A. M. U. Aligarh, 202002, India
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