Dataset Information

Decoding the absolute stoichiometric composition and structural plasticity of α-carboxysomes

ABSTRACT: Carboxysomes are anabolic bacterial microcompartments that play an essential role in carbon fixation in cyanobacteria and some chemoautotrophs. This self-assembling organelle encapsulates the key CO2-fixing enzymes, Rubisco, and carbonic anhydrase using a polyhedral protein shell that is constructed by hundreds of shell protein paralogs. The α-carboxysome from the chemoautotroph Halothiobacillus neapolitanus serves as a model system in fundamental studies and synthetic engineering of carboxysomes. Here we adopt a QconCAT-based quantitative mass spectrometry approach to determine the stoichiometric composition of native α-carboxysomes from H. neapolitanus. We further performed an in-depth comparison of the protein stoichiometry of native and recombinant α-carboxysomes heterologously generated in Escherichia coli to evaluate the structural variability and remodeling of α-carboxysomes. Our results provide insight into the molecular principles that mediate carboxysome assembly, which may aid in rational design and reprogramming of carboxysomes in new contexts for biotechnological applications

INSTRUMENT(S): Q Exactive HF

ORGANISM(S): Halothiobacillus Neapolitanus C2

SUBMITTER: Philip Brownridge

LAB HEAD: Professor Luning Liu

PROVIDER: PXD031420 | Pride | 2022-05-20

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	VH_101120_Native_1_only_1hr.mgf	Mgf
	VH_101120_Native_1_only_1hr.raw	Raw
	VH_101120_Native_1_only_1hr_ecoli.mzid.gz	Mzid
	VH_101120_Native_1_only_1hr_halo.mzid.gz	Mzid
	VH_101120_Native_2_only_1hr.mgf	Mgf

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Publications

Decoding the Absolute Stoichiometric Composition and Structural Plasticity of α-Carboxysomes.

Sun Yaqi Y Harman Victoria M VM Johnson James R JR Brownridge Philip J PJ Chen Taiyu T Dykes Gregory F GF Lin Yongjun Y Beynon Robert J RJ Liu Lu-Ning LN

mBio 20220328 2

Carboxysomes are anabolic bacterial microcompartments that play an essential role in carbon fixation in cyanobacteria and some chemoautotrophs. This self-assembling organelle encapsulates the key CO<sub>2</sub>-fixing enzymes, Rubisco, and carbonic anhydrase using a polyhedral protein shell that is constructed by hundreds of shell protein paralogs. The α-carboxysome from the chemoautotroph Halothiobacillus neapolitanus serves as a model system in fundamental studies and synthetic engineering of ...[more]

PMID: 35343789

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