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. 2002 Apr;82(4):2184–2197. doi: 10.1016/S0006-3495(02)75565-3

Absorption and CD spectroscopy and modeling of various LH2 complexes from purple bacteria.

Sofia Georgakopoulou 1, Raoul N Frese 1, Evelyn Johnson 1, Corline Koolhaas 1, Richard J Cogdell 1, Rienk van Grondelle 1, Gert van der Zwan 1
PMCID: PMC1302012  PMID: 11916874

Abstract

The absorption (OD) and circular dichroism (CD) spectra of LH2 complexes from various purple bacteria have been measured and modeled. Based on the lineshapes of the spectra we can sort the LH2 complexes into two distinguishable groups: "acidophila"-like (type 1) and "molischianum"-like (type 2). Starting from the known geometric structures of Rhodopseudomonas (Rps.) acidophila and Rhodospirillum (Rsp.) molischianum we can model the OD and CD spectra of all species by just slightly varying some key parameters: the interaction strength, the energy difference of alpha- and beta-bound B850 bacteriochlorophylls (BChls), the orientation of the B800 and B850 BChls, and the (in)homogeneous broadening. Although the ring size can vary, the data are consistent with all the LH2 complexes having basically very similar structures.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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