多样化的移动遗传元素之间的复杂相互作用推动了耐金属细菌基因组的进化
Khandaker Rayhan Mahbub1, Caroline Chénard2, Steven Batinovic3
1School of Life Sciences, University of Technology Sydney, Ultimo, New South Wales, Australia.
Environmental microbiology
|November 2, 2023
概括
新型移动遗传元素 (MGE) 和水平基因转移 (LGT) 驱动了污染土壤中的细菌对金属的抗性. 这些MGE,包括基因组岛屿和转位子,促进适应重金属.
科学领域:
- 微生物学 微生物学
- 基因组学就是基因组学.
- 环境科学 环境科学
背景情况:
- 土壤中的金属污染对生态系统和人类健康构成风险.
- 在受污染的环境中,细菌进化了抵抗机制以求生存.
- 已知移动遗传元素 (MGE) 在抗生素和金属耐药性的传播中起作用.
研究的目的:
- 为了比较从污染的土壤中分离出来的三种耐金属细菌的基因组.
- 识别新型MGE并了解它们在重金属抵抗中的作用.
- 研究横向基因转移 (LGT) 对细菌适应金属污染环境的影响.
主要方法:
- 使用Illumina和牛津纳米孔技术进行全基因组测序.
- 对三种细菌菌株进行比较基因组分析:斯芬戈比亚 sp SA2 ,斯芬戈皮克西斯 sp SE2 和伪索莫纳斯 sp SE1.
- 移动遗传元素 (MGE) 和金属抗性基因的注释.
主要成果:
- 确定了多样化和新型的MGE,包括基因组岛屿 (GI),整合性结合元件 (ICE),转位子,插入序列 (IS),三组 (RIT) 元素中的重组酶和II组内基因.
- Sphingobium sp SA2和Sphingopyxis sp SE2表现出对多种金属的耐药性,并拥有与MGE相关的众多金属耐药性基因.
- 伪类人种SE1只对有耐药性,其金属耐药性区域主要位于GI上,总体上耐药性基因较少.
- 证据表明多个LGT事件塑造了细菌的基因组结构和金属耐药性.
结论:
- 新型MGE对于来自受污染环境的细菌获得和传播重金属耐药性至关重要.
- LGT是一个重要的进化力量,驱动细菌适应金属污染.
- 鉴定到的MGEs提供了关于重金属污染土壤中细菌生存和耐药性的复杂机制的见解.
相关概念视频
Genome Size and the Evolution of New Genes
8.0K
While every living organism has a genome of some kind (be it RNA, or DNA), there is considerable variation in the sizes of these blueprints. One major factor that impacts genome size is whether the organism is prokaryotic or eukaryotic. In prokaryotes, the genome contains little to no non-coding sequence, such that genes are tightly clustered in groups or operons sequentially along the chromosome. Conversely, the genes in eukaryotes are punctuated by long stretches of non-coding sequence.
8.0K
Antibiotic Selection
54.4K
Overview
54.4K
Transduction
21
Among the three main modes of HGT—transformation, conjugation, and transduction—transduction is unique in that it is mediated by bacteriophages, or bacterial viruses.Transduction occurs in two ways. Generalized transduction occurs during the lytic cycle of a bacteriophage infection. In this process, bacteriophages infect bacterial cells, replicate within them, and ultimately cause cell lysis, releasing newly assembled virions. Occasionally, random fragments of the bacterial genome...
21
Transposons
38
Transposons, or "jumping genes," are small mobile genetic elements (MGEs) that range from 700 to 40,000 base pairs in length. They are found in all organisms and can move within the same chromosome or transfer to different chromosomes. In some cases, transposons can also jump between different host DNA molecules, such as plasmids or viruses, contributing to genetic variability.Barbara McClintock first discovered these mobile genetic elements in the 1940s while studying maize genetics, and she...
38
Genomic DNA in Prokaryotes
43.9K
The genome of most prokaryotic organisms consists of double-stranded DNA organized into one circular chromosome in a region of cytoplasm called the nucleoid. The chromosome is tightly wound, or supercoiled, for efficient storage. Prokaryotes also contain other circular pieces of DNA called plasmids. These plasmids are smaller than the chromosome and often carry genes that confer adaptive functions, such as antibiotic resistance.
Genomic Diversity in Bacteria
Although bacterial genomes are much...
Genomic Diversity in Bacteria
Although bacterial genomes are much...
43.9K
Other Unique Bacteria
19
Magnetic bacteria exhibit a directed movement called magnetotaxis, driven by structures called magnetosomes. These magnetosomes consist of chains of magnetic particles made of either magnetite (Fe₃O₄) or greigite (Fe₃S₄) and are organized in a linear conformation by a protein scaffold within invaginations of the cell membrane. The bacteria align along the north–south magnetic field lines, much like a compass needle. They are typically microaerophilic or anaerobic...
19


