Final answer:
Particles known as gene transfer agents enable the horizontal gene transfer of genetic material in marine prokaryotes, moving random genomic segments between species. Other HGT mechanisms include transformation, transduction by bacteriophages, and conjugation via a pilus.
Step-by-step explanation:
Possible Mechanisms of Gene Transfer in Marine Prokaryotes
Particles that transfer genetic material from one species to another, especially in marine prokaryotes, are described by small, virus-like particles known as gene transfer agents (GTAs). GTAs facilitate the horizontal gene transfer (HGT) by moving random genomic segments from one prokaryotic species to another. This type of genetic exchange is a key driver in prokaryotic evolution and can occur at a very high frequency.
Horizontal gene transfer in prokaryotes can also occur through other mechanisms, such as transformation, where the prokaryote takes up DNA directly from the environment. Another method is transduction, which involves bacteriophages transferring DNA between bacteria. Finally, conjugation allows the transfer of DNA via a pilus between two prokaryotes. While transduction and conjugation involve more specific and directed mechanisms of gene transfer, GTAs are unique in their random transfer of genetic material, contributing significantly to genetic diversity in prokaryotic populations.