Related Experiment Video
Updated: Dec 10, 2025
08:07
A Micropatterning Assay for Measuring Cell Chirality
Published on: March 11, 2022
2.6K
Symmetry breaking and structural polymorphism in a bacterial microcompartment shell protein for choline utilization.
Jessica M Ochoa1, Vy N Nguyen2, Mengxiao Nie2
1UCLA-Molecular Biology Institute, University of California, Los Angeles (UCLA), California, Los Angeles, USA.
Protein Science : a Publication of the Protein Society
|September 5, 2020
Summary
Bacterial microcompartment (BMC) protein structures reveal novel assembly mechanisms. This study shows how variations in BMC protein architecture enable flexible shell construction in bacteria.
Area of Science:
- Biochemistry
- Structural Biology
- Microbiology
Background:
- Bacterial microcompartments (BMC) are protein-based organelles essential for specialized metabolic functions.
- Their shells, composed of thousands of protein subunits, assemble via principles like hexameric BMC protein packing.
- Polymorphic assembly mechanisms have hindered a complete understanding of BMC shell architecture.
Purpose of the Study:
- To investigate the quaternary architectures of BMC shell proteins, specifically CutR from Streptococcus intermedius.
- To explore the structural basis for flexible assembly modes in BMC shells.
- To elucidate the role of the EutS/PduU/CutR subfamily in BMC shell construction.
Main Methods:
- X-ray crystallography to determine the structure of CutR under various conditions.
- Analysis of different crystal forms, expression constructs, and minor mutations.
- Development of a novel graphical approach to visualize BMC hexameric structure variations.
Main Results:
- Reported crystal structures of CutR revealing novel quaternary architectures, including spiral hexagonal assemblies.
- Demonstrated polymorphic assembly mechanisms influenced by crystal form, expression construct, and mutations.
- Substantiated that the EutS/PduU/CutR subfamily exhibits flexible assembly capabilities.
Conclusions:
- The EutS/PduU/CutR subfamily of BMC proteins provides flexible assembly modes for bacterial microcompartment shells.
- Understanding these diverse architectures is crucial for comprehending BMC function and evolution.
- This work offers new insights into the structural plasticity of protein-based organelles.
Related Concept Videos
02:30Chirality in Nature
16.2K
Chirality is the most intriguing yet essential facet of nature, governing life’s biochemical processes and precision. It can be observed from a snail shell pattern in a macroscopic world to an amino acid, the minutest building block of life. Most of the snails around the world have right-coiled shells because of the intrinsic chirality in their genes. All the amino acids present in the human body exist in an enantiomerically pure state, except for glycine - the sole achiral amino acid.
16.2K
02:25Chirality
28.6K
Chirality is a term that describes the lack of mirror symmetry in an object. In other words, chiral objects cannot be superposed on their mirror images. For example, our feet are chiral, as the mirror image of the left foot, the right foot, cannot be superposed on the left foot.
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
28.6K
01:35Asymmetric Lipid Bilayer
9.3K
Biological membranes show uneven distribution of different types of lipids in the inner and outer layers, resulting in transverse asymmetric membranes. The treatment of the erythrocyte membrane with the enzyme phospholipase confirmed the asymmetric nature of the lipid bilayer. The enzyme hydrolyzes lipids into fatty acids and hydrophilic groups. The phospholipase acts only on the outer layer of the membrane, while the inner layer remains intact. The phospholipase treatment resulted in 80%...
9.3K
01:19Membrane Asymmetry Regulating Transporters
6.7K
Enzymes like flippase, floppase, and scramblase transfer phospholipids from one layer to another in the membrane, thereby affecting membrane asymmetry.
Flippase
Eukaryotic flippases are type-IV P-type ATPases or P4-ATPases belonging to P-type ATPase family proteins that are membrane-bound pumps involved in the ATP-mediated transport of ions and molecules across the membrane. Flippases flip specific phospholipids from the outer to the inner leaflet of a membrane. All P4-ATPases have one...
Flippase
Eukaryotic flippases are type-IV P-type ATPases or P4-ATPases belonging to P-type ATPase family proteins that are membrane-bound pumps involved in the ATP-mediated transport of ions and molecules across the membrane. Flippases flip specific phospholipids from the outer to the inner leaflet of a membrane. All P4-ATPases have one...
6.7K
01:29Cytoskeletal Proteins in Bacteria
4.0K
Bacterial cells were initially considered simple, randomly organized structures lacking a cytoskeleton. However, the discovery of cytoskeleton homologs in bacteria led to the change of this opinion. Bacterial cytoskeletal filaments regulate the cell shape, cell polarity, cell division, and partitioning of plasmids during cell division. It was later discovered that bacterial cytoskeletal proteins, mainly actin and tubulin homologs, are diverse compared to their eukaryotic counterparts. On the...
4.0K
02:25Molecules with Multiple Chiral Centers
14.5K
Molecules that possess multiple chiral centers can afford a large number of stereoisomers. For instance, while some molecules like 2-butanol have one chiral center, defined as a tetrahedral carbon atom with four different substituents attached, several molecules like butane-2,3-diol have multiple chiral centers. A simple formula to predict the number of stereoisomers possible for a molecule with n chiral centers is 2n. However, there can be a lower number where some of the stereoisomers are...
14.5K