Difference between revisions of "Part:BBa K5246026"

Revision as of 09:31, 29 September 2024

CB2/CB2A HfsH Deacetylase, 6xHis tag for purification

Introduction

Usage and Biology

TBA

This part also has a non his-tagged variant BBa_K5246008.

Sequence and Features

Experimental characterization

Bioinformatic analysis

CDD and protein BLAST analysis suggest that HfsG is a glucosyltransferase family 2 protein. Proteins of this family are involved in cell wall biosynthesis. HfsG is similar to the WecA protein in E.Coli that catalyzes the transfer of the GlcNAc-1-phosphate moiety from UDP-GlcNAc onto the carrier lipid undecaprenyl phosphate. In the case of HfsG, it catalyzes the transfer of UDP-GlcNAc to the sugar acceptor made earlier in the holdfast synthesis pathway.

Protein topology analysis using DeepTMHMM suggests that HfsG is a globular protein located in the cytoplasm. AlphaFold 3 structures further confirm it. A pTM score above 0.5 suggests that the predicted overall structure may closely resemble the true protein fold, while ipTM indicates the accuracy of the subunit positioning within the complex. Values higher than 0.8 represent confident, high-quality predictions.

HfsG is family 2 glycosyltransferase similar to WecA of E.Coli. This globular protein transfers UDP-GlcNAc to the acceptor molecule, our conclusions are in agreement with existing research. [1][2][3]

Protein purification

CB2 strain

After successful expression, we proceeded to work on the purification of his-tagged proteins. We went with immobilized metal ion affinity chromatography (IMAC). Adapting protocols from the little research that was available, we used HisPur Ni-NTA Spin Columns (Thermo Scientific). Equilibration, wash, and elution buffers contained 10 mM Tris pH 7.4, 150 mM NaCl, and 10 mM, 75 mM, and 500 mM imidazole, respectively.

HfsH is purifyable and clearly seen in the gel elution fraction. HfsH could migrate higher than its expected size because the higher the positive charge density (more charges per molecule mass), the slower a protein will migrate. At the same time, the frictional force of the gel matrix creates a sieving effect, regulating the movement of proteins according to their size and three-dimensional shape. HfsH has a high density of positively charged amino acids causing its unexpected migration in the gel

CB2A strain

After successful expression, we proceeded to work on the purification of his-tagged proteins. We went with immobilized metal ion affinity chromatography (IMAC). Adapting protocols from the little research that was available, we used HisPur Ni-NTA Spin Columns (Thermo Scientific). Equilibration, wash, and elution buffers contained 10 mM Tris pH 7.4, 150 mM NaCl, and 10 mM, 75 mM, and 500 mM imidazole, respectively.

HfsH is purifyable and clearly seen in the gel elution fraction. HfsH could migrate higher than its expected size because the higher the positive charge density (more charges per molecule mass), the slower a protein will migrate. At the same time, the frictional force of the gel matrix creates a sieving effect, regulating the movement of proteins according to their size and three-dimensional shape. HfsH has a high density of positively charged amino acids causing its unexpected migration in the gel.

References

1. Hendrickson, H., & Lawrence, J. G. (2000). Mutational bias suggests that replication termination occurs near the dif site, not at Ter sites. FEMS Microbiology Reviews, 24(2), 177–183. https://doi.org/10.1111/j.1574-6976.2000.tb00539.x
2. Andrews, S. C., Robinson, A. K., & Rodríguez-Quiñones, F. (2004). Bacterial iron homeostasis. Journal of Bacteriology, 186(5), 1438–1447. https://doi.org/10.1128/jb.186.5.1438-1447.2004
3.Rabah, A., & Hanchi, S. (2023). Experimental and modeling study of the rheological and thermophysical properties of molybdenum disulfide-based nanofluids. Journal of Molecular Liquids, 384, 123335. https://doi.org/10.1016/j.molliq.2023.123335
4. Boutte, C. C., & Crosson, S. (2009). Bacterial lifestyle shapes stringent response activation. Journal of Bacteriology, 191(9), 2904-2912. https://doi.org/10.1128/jb.01003-08
5. Mackie, J., Liu, Y. C., & DiBartolo, G. (2019). The C-terminal region of the Caulobacter crescentus CtrA protein inhibits stalk synthesis during the G1-to-S transition. mBio, 10(2), e02273-18. https://doi.org/10.1128/mbio.02273-18
6.Thanbichler, M., & Shapiro, L. (2003). MipZ, a spatial regulator coordinating chromosome segregation with cell division in Caulobacter. Journal of Bacteriology, 185(4), 1432-1442. https://doi.org/10.1128/jb.185.4.1432-1442.2003
7. Toh, E., Kurtz, Harry D. and Brun, Y.V. (2008) ‘Characterization of the Caulobacter crescentus holdfast polysaccharide biosynthesis pathway reveals significant redundancy in the initiating glycosyltransferase and polymerase steps’, Journal of Bacteriology, 190(21), pp. 7219–7231. doi:10.1128/jb.01003-08.
8. Chepkwony, N.K., Berne, C. and Brun, Y.V. (2019b) ‘Comparative analysis of ionic strength tolerance between freshwater and marine Caulobacterales adhesins’, Journal of Bacteriology, 201(18). doi:10.1128/jb.00061-19.