Abstract:

As one of the most fundamental environmental rhythms on earth， light-dark alternation exerts a profound impact on the survival and functions of microorganisms in both natural and artificial environments. Microbes have evolved a series of sophisticated and complex response mechanisms to adapt to such periodic changes in energy and information input. This review systematically summarized the multi-dimensional response mechanisms of microorganisms at the metabolic， transcriptional， and protein levels under light-dark alternation conditions. At the metabolic level， microorganisms dynamically regulate central carbon metabolism， energy metabolism， and redox balance to optimize energy acquisition and substance synthesis. At the transcriptional level， with circadian clock gene networks and light-sensing signal transduction pathways as the core， they globally reprogram gene expression to achieve orderly regulation in the temporal dimension. At the protein level， they rapidly perform adaptive functions through strategies such as post-translational modification， protein stability regulation， and dynamic assembly of protein complexes. This review focused on the interaction and integration of the response mechanisms at these three levels， revealed their inherent temporal and network characteristics， and looked forward to their application prospects in fields such as synthetic biology， biomanufacturing， and environmental remediation.

Key words: light-dark alternation, microorganism, metabolic reprogramming, transcriptional regulation, proteome