Difference between revisions of "Part:BBa K1640008"

Latest revision as of 01:35, 19 September 2015

psbMZH

Sequence and Features

Overview

This biobrick contains three genes from the photosystem II complex of Chlamydomonas reinhardtii - psbM, psbZ, and psbH, with RBS preceeding each gene, and lac promoter driving expression.

- PsbM is a Photosystem II core complex subunit.
- PsbZ is a stabilising protein for the Photosystem II/Light Harvesting Complex II supercomplex.
- PsbH is another Photosystem II core complex subunit.

This part was designed in conjunction with BBa_K1640021, and together they form operon 4 in our set of photosystem II operons:

Biology & Literature

PsbM encodes a highly hydrophobic protein, psbM, with a single, membrane spanning α-helix located at the monomer-monomer interface of PSII (Ferreira, Iverson, Maghlaoui, Barber, & Iwata, 2004). This proteins acts to stabilise the dimerization of PSII. While not a necessary factor for PSII biosynthesis, its absence weakens the dimer interconnection of the core complex, and may impair PSII repair (Umate et al., 2007). Deletion studies of this gene have shown a 28% decrease in successfully assembled PSII centres (Bentley, Luo, Dilbeck, Burnap, & Eaton-Rye, 2008).

PsbZ, also referred to as ycf9, is a highly conserved gene amongst photosynthetic species, encoding a two transmembrane helix protein, psbZ (Ferreira et al., 2004). PsbZ is found at the interface between PSII and light harvesting complex II (LHCII). (Minagawa & Takahashi, 2004). Deletion studies of psbZ have resulted in decreased stability of the PSII-LHCII supercomplex, suggesting this protein is involved in anchoring the two complexes (Swiatek et al., 2001).

PsbH encodes a low molecular weight PSII subunit, psbH, containing multiple phosphorylation sites (Vener, Harms, Sussman, & Vierstra, 2001). Deletion studies of this gene across multiple species have shown different effects. In Synechocystis sp., a slower growth rate, higher light sensitivity, and impaired electron transport from QA to QB has been observed (Mayes et al., 1993). In addition, the deletion of psbH has been observed to both destabilize the PSII complex, and impair the binding of bicarbonate to the complex (Komenda, Lupínková, & Kopecký, 2002), and in Chlamydomonas reinhardtii, eliminate the formation of the PSII complex, revealing psbH as a vital gene for the synthesis of Photosystem II (Summer, Schmid, Bruns, & Schmidt, 1997).

Protein information

psbM

mass: 3.76kDa

sequence: MEVNIYGLTATALFIIIPTSFLLILYVKTASTQD

psbZ

mass: 4.56kDa

sequence: MVGVPVVFATPNGWTDNKGAVFSGLSLWLLLVFVVGILNSFVV

psbH

mass: 6.02kDa

sequence: MSEAGKVLPGWGTTVLMAVFILLFAAFLLIILEIYNSSLILDDVSMSWETLAKVS

Part verification

Visualisation of psbMZH showing expected banding is shown in the following gel image, rightmost set of lanes, with left lane part showing EcoRI digest, right lane showing EcoRI + PstI double digest. This part has been sequenced to confirm design with final biobrick.

References

Bentley, F. K., Luo, H., Dilbeck, P., Burnap, R. L., & Eaton-Rye, J. J. (2008). Effects of Inactivating psbM and psbT on Photodamage and Assembly of Photosystem II in Synechocystis sp. PCC 6803†. Biochemistry, 47(44), 11637-11646.

Ferreira, K. N., Iverson, T. M., Maghlaoui, K., Barber, J., & Iwata, S. (2004). Architecture of the Photosynthetic Oxygen-Evolving Center. Science, 303(5665), 1831-1838. doi:10.1126/science.1093087

Komenda, J., Lupínková, L., & Kopecký, J. (2002). Absence of the psbH gene product destabilizes photosystem II complex and bicarbonate binding on its acceptor side in Synechocystis PCC 6803. European Journal of Biochemistry, 269(2), 610-619. doi:10.1046/j.0014-2956.2001.02693.x

Mayes, S. R., Dubbs, J. M., Vass, I., Hideg, E., Nagy, L., & Barber, J. (1993). Further characterization of the psbH locus of Synechocystis sp. PCC 6803: inactivation of psbH impairs QA to QB electron transport in photosystem 2. Biochemistry, 32(6), 1454-1465.

Minagawa, J., & Takahashi, Y. (2004). Structure, function and assembly of Photosystem II and its light-harvesting proteins. Photosynthesis Research, 82(3), 241-263. doi:10.1007/s11120-004-2079-2

Summer, E. J., Schmid, V. H., Bruns, B. U., & Schmidt, G. W. (1997). Requirement for the H phosphoprotein in photosystem II of Chlamydomonas reinhardtii. Plant physiology, 113(4), 1359-1368.

Swiatek, M., Kuras, R., Sokolenko, A., Higgs, D., Olive, J., Cinque, G., . . . Bassi, R. (2001). The chloroplast gene ycf9 encodes a photosystem II (PSII) core subunit, PsbZ, that participates in PSII supramolecular architecture. The Plant Cell, 13(6), 1347-1368.

Umate, P., Schwenkert, S., Karbat, I., Dal Bosco, C., Mlcòchová, L., Volz, S., . . . Meurer, J. (2007). Deletion of PsbM in tobacco alters the QB site properties and the electron flow within photosystem II. Journal of Biological Chemistry, 282(13), 9758-9767.

Vener, A. V., Harms, A., Sussman, M. R., & Vierstra, R. D. (2001). Mass spectrometric resolution of reversible protein phosphorylation in photosynthetic membranes ofArabidopsis thaliana. Journal of Biological Chemistry, 276(10), 6959-6966.