相关实验视频

Updated: Jun 16, 2025

The Lambda Select cII Mutation Detection System

The Lambda Select cII Mutation Detection System

Published on: April 26, 2018

科利巴克导致细菌特异性的突变模式和自我造成的DNA损伤

Emily Lowry¹, Yiqing Wang², Tal Dagan²

¹Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, Massachusetts 01605, USA.

Genome research

|August 16, 2024

概括

科利巴克丁是大肠杆菌中的毒素,它会破坏细菌DNA,导致独特的突变. 这项研究揭示了细菌如何应对这种自我损伤及其基因组后果.

科学领域:

微生物学微生物学
基因组学就是基因组学.
癌症研究癌症研究

背景情况:

由大肠杆菌 (Escherichia coli) 生产的可利巴克是一种交叉链接DNA的基因毒素,与结肠癌有关.
了解 colibactin 对产生的细菌本身的影响对于理解其整体影响至关重要.

研究的目的:

为了研究缓解大肠杆菌中大肠杆菌诱导的DNA损伤的细胞通路.
为了确定细菌基因组内由 colibactin 诱导的特定突变模式.
为了确定是否有 colibactin 暴露导致了 E. coli 中的三核酸组成的基因组偏差.

主要方法:

用全基因组基因选来识别细菌耐药机制.
进行了突变积累实验,以观察 colibactin 诱导的突变.
对数千个大肠杆菌基因组进行了分析,以评估三核酸组成偏差.

主要成果:

科利巴克丁向A/T丰富的基因,类似于它在人体细胞中的作用,但会诱导一种独特的细菌突变模式.
在生产大肠杆菌菌株中观察到三核酸组成的基因组偏差.
colibactin 病原性岛上的耐药性蛋白似乎不足以完全防止自我造成的 DNA 损伤.

结论:

科利巴克诱导细菌特异性的DNA损伤和突变模式.
长期暴露于 colibactin 导致三核酸组合的可预测的基因组倾斜性.
细菌对抗 colibactin 的防御机制并不完全有效,导致正在进行的基因组改变.

更多相关视频

Imaging Mismatch Repair and Cellular Responses to DNA Damage in Bacillus subtilis

Imaging Mismatch Repair and Cellular Responses to DNA Damage in Bacillus subtilis

Published on: February 8, 2010

Generating Transposon Insertion Libraries in Gram-Negative Bacteria for High-Throughput Sequencing

Generating Transposon Insertion Libraries in Gram-Negative Bacteria for High-Throughput Sequencing

Published on: July 7, 2020

相关概念视频

Genome Copying Errors

Genome Copying Errors

DNA replication is a well-evolved process that copies millions of base pairs with high fidelity during each cell division. Occasionally a wrong base or a long stretch of wrong bases may get added to the daughter strands. If the errors are left unchecked, cells might accumulate several mutations that might endanger their survival. Therefore, the copying errors are checked and repaired at three levels.

Mismatch Repair

Mismatch Repair

Organisms are capable of detecting and fixing nucleotide mismatches that occur during DNA replication. This sophisticated process requires identifying the new strand and replacing the erroneous bases with correct nucleotides. Mismatch repair is coordinated by many proteins in both prokaryotes and eukaryotes.
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...

Nucleotide Excision Repair

Nucleotide Excision Repair

Antibiotic Selection

Antibiotic Selection

Translesion DNA Polymerases

Translesion DNA Polymerases

Translesion (TLS) polymerases rescue stalled DNA polymerases at sites of damaged bases by replacing the replicative polymerase and installing a nucleotide across the damaged site. Doing so, TLS allows additional time for the cell to repair the damage before resuming regular DNA replication.
TLS polymerases are found in all three domains of life - archaea, bacteria, and eukaryotes. Of the different classes of TLS polymerases, members of the Y family are fitted with specialized structures that...

Fixing Double-strand Breaks

Fixing Double-strand Breaks

The double-stranded structure of DNA has two major advantages. First, it serves as a safe repository of genetic information where one strand serves as the back-up in case the other strand is damaged. Second, the double-helical structure can be wrapped around proteins called histones to form nucleosomes, which can then be tightly wound to form chromosomes. This way, DNA chains up to 2 inches long can be contained within microscopic structures in a cell. A double-stranded break not only damages...