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  • The minimal SUF system is not required for Fe–S cluster biogenesis in the methanogenic archaeon Methanosarcina acetivorans
Title: The minimal SUF system is not required for Fe–S cluster biogenesis in the methanogenic archaeon Methanosarcina acetivorans
Abstract Iron–sulfur (Fe–S) proteins are essential for the ability of methanogens to carry out methanogenesis and biological nitrogen fixation (diazotrophy). Nonetheless, the factors involved in Fe–S cluster biogenesis in methanogens remain largely unknown. The minimal SUF Fe–S cluster biogenesis system (i.e., SufBC) is postulated to serve as the primary system in methanogens. Here, the role of SufBC inMethanosarcina acetivorans, which contains twosufCBgene clusters, was investigated. The CRISPRi-dCas9 and CRISPR-Cas9 systems were utilized to repress or deletesufC1B1andsufC2B2, respectively. Neither the dual repression ofsufC1B1andsufC2B2nor the deletion of bothsufC1B1andsufC2B2affected the growth ofM. acetivoransunder any conditions tested, including diazotrophy. Interestingly, deletion of onlysufC1B1led to a delayed-growth phenotype under all growth conditions, suggesting that the deletion ofsufC2B2acts as a suppressor mutation in the absence ofsufC1B1. In addition, the deletion ofsufC1B1and/orsufC2B2did not affect the total Fe–S cluster content inM. acetivoranscells. Overall, these results reveal that the minimal SUF system is not required for Fe–S cluster biogenesis inM. acetivoransand challenge the universal role of SufBC in Fe–S cluster biogenesis in methanogens.  more » « less
Award ID(s):
1817819
PAR ID:
10462477
Author(s) / Creator(s):
; ;
Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
Scientific Reports
Volume:
13
Issue:
1
ISSN:
2045-2322
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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