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Cryo-EM particle stacks of the ∆KsgA immature 30S sample

ABSTRACT:

SUBMITTER: Joseph Davis

PROVIDER: EMPIAR-11529 | biostudies-other |

REPOSITORIES: biostudies-other

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KsgA facilitates ribosomal small subunit maturation by proofreading a key structural lesion.

Sun Jingyu J Kinman Laurel F LF Jahagirdar Dushyant D Ortega Joaquin J Davis Joseph H JH

Nature structural & molecular biology 20230831 10

Ribosome assembly is orchestrated by many assembly factors, including ribosomal RNA methyltransferases, whose precise role is poorly understood. Here, we leverage the power of cryo-EM and machine learning to discover that the E. coli methyltransferase KsgA performs a 'proofreading' function in the assembly of the small ribosomal subunit by recognizing and partially disassembling particles that have matured but are not competent for translation. We propose that this activity allows inactive parti ...[more]

PMID: 37653244

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