H‐NS, IHF, and DnaA lead to changes in nucleoid organizations, replication initiation, and cell division. (5th November 2019)

• Record Type: Journal Article
• Authors: Huang, Tingting; Yuan, Hong; Fan, Lifei; Morigen, Morigen
• Is Part Of: Journal of basic microbiology. Volume 60:issue 2(2020)
• Page Start: 136
• Page End: 148
• Publication Date: 2019-11-05
• Subjects: cell division -- DnaA -- H‐NS -- HU -- IHF -- nucleoid organization -- replication initiation; Microbiology -- Periodicals; 579
• DOI: 10.1002/jobm.201900497
• Languages: English
• ISSNs: 0233-111X

Abstract

Abstract: Histone‐like nucleoid‐structuring protein (H‐NS) and integration host factor (IHF) are major nucleoid‐associated proteins, and DnaA, a replication initiator, may also be related with nucleoid compaction. It has been shown that protein‐dependent DNA compaction is related with many aspects of bacterial physiology, including transcription, DNA replication, and site‐specific recombination. However, the mechanism of bacterial physiology resulting from nucleoid compaction remains unknown. Here, we show that H‐NS is important for correct nucleoid compaction in a medium‐independent manner. H‐NS‐mediated nucleoid compaction is not required for correct cell division, but the latter is dependent on H‐NS in rich medium. Further, it is found that the IHFα‐mediated nucleoid compaction is needed for correct cell division, and the effect is dependent on medium. Also, we show that the effects of H‐NS and IHF on nucleoid compaction are cumulative. Interestingly, DnaA also plays an important role in nucleoid compaction, and the effect of DnaA on nucleoid compaction appears to be related to cell division in a medium‐dependent manner. The results presented here suggest that scrambled initiation of replication, improper cell division, and slow growth is likely associated with disturbances in nucleoid organization directly or indirectly.