Final answer:
Heteroduplex DNA refers to DNA composed of strands from different origins, created during bacterial transformation, a type of horizontal gene transfer. Single-stranded DNA is less prone to nuclease degradation and can integrate into the host genome, potentially leading to the spread of traits like antibiotic resistance.
Step-by-step explanation:
The term heteroduplex refers to a DNA molecule that consists of two strands originating from different sources, often as a result of genetic recombination. During bacterial transformation, a process of horizontal gene transfer (HGT), a bacterium takes up foreign DNA from its environment. This environmental DNA, once inside the cell, is made single-stranded to avoid degradation by nucleases and to facilitate its integration into the bacterial chromosome. If integration occurs, this can lead to a bacterium with newly acquired phenotypic traits, such as antibiotic resistance or virulence factors. In the context of medical settings, this provides a concern as it might contribute to the spread of antibiotic resistance among bacterial populations.
A bacterial cell transforms environmental DNA into a single-stranded form because this form is less susceptible to nuclease activity, which is a bacterial defense mechanism against viral infection. Single-stranded DNA can recombine into the bacterial genome more readily, allowing the cell to potentially acquire beneficial genes. This is also a mechanism by which antibiotic resistance genes spread in bacterial populations, underlining the importance of monitoring and understanding transformation in healthcare.