BACTERIAL MULTIENZYMATIC COMPLEXES REGULATING CELL HOMEOSTASIS IN RESPONSE TO ENVIRONMENTAL STRESSES

• Grant number: 19/08514-0
• Support Opportunities: Regular Research Grants
• Start date: September 01, 2019
• End date: February 28, 2022
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Marilis Do Valle Marques
• Grantee: Marilis Do Valle Marques
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated researchers: Marcio Vinicius Bertacine Dias ; Tie Koide

Abstract

Caulobacter crescentus is an oligotrophic alpha-proteobacterium important for recycling of organic matter generated mainly from decomposing plants. This bacterium is well adapted to survive in low nutrient environments and at low temperature, and has a differentiation step in its cell cycle. Multienzymatic complexes have vital roles in cell survival, mainly under stress conditions, where each protein has a specific function in the complex, and collaborates for the final result. At low temperature, RNA molecules are prone to form stable secondary structures, impairing its translation and degradation, and RNA helicases are activated, sometimes associated to the RNA degradosome. The RNA degradosome is a multienzymatic complex that acts in the ribosomal RNA processing and mRNA degradation, therefore affecting gene expression. The TonB-ExbB-ExbD-Receptor is a multienzymatic complex involved in intracellular iron homeostasis, and is responsible for the transport of iron-siderophores complexes through the bacterial outer membrane. The main goal of this project is to determine the role of some participants of these protein complexes in C. crescentus. The role of the DEAD-box RNA helicases in the processing of cell RNAs will be evaluated under distinct growth conditions through global transcriptomics analyses. Moreover, the RNAs, particularly sRNAs and mRNAs, that interact with the degradosome will be identified, as well as the site of interaction of the helicase with the degradosome. In order to study the iron transport systems, this project proposed to identify the roles of distinct components from this system, the ferric complex transported, to characterize the transport kinetics and determining the structure and function of accessory proteins that are yet poorly studied. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

KUMAR, ASHISH; YANG, TAIHAO; CHAKRAVORTY, SOMNATH; MAJUMDAR, ARITRI; NAIRN, BRITTANY L.; SIX, DAVID A.; DOS SANTOS, NAARA MARCONDES; PRICE, SARAH L.; LAWRENZ, MATTHEW B.; ACTIS, LUIS A.; et al. Fluorescent sensors of siderophores produced by bacterial pathogens. Journal of Biological Chemistry, v. 298, n. 3, p. 16-pg., 2022-03-01. (19/08514-0)

DE ARAUJO, HUGO L.; MARTINS, BIANCA P.; VICENTE, ALEXANDRE M.; LORENZETTI, ALAN P. R.; KOIDE, TIE; MARQUES, V, MARILIS. Cold Regulation of Genes Encoding Ion Transport Systems in the Oligotrophic Bacterium Caulobacter crescentus. MICROBIOLOGY SPECTRUM, v. 9, n. 1, SEP 2021. (19/08514-0, 18/17309-8, 19/13440-5, 14/13552-4, 17/03052-2)