J P Allen's research while affiliated with Arizona State University and other places

... The long-lived P + Q A state in bRCs has recently been shown to be linked to the proton release capability of a hydrogenbond network that is formed by amino acid residues and bound water molecules near P (Allen et al., 2023). These regions, and similar networks in PSII, are proposed to be involved in the polarization of the RC matrix and thus in the dielectric relaxation processes . ...

... Hybrid complexes with protein domains having novel molecules as bound cofactors have been employed as a strategy for producing functional proteins that recognize molecular features or are capable of performing energy transfer (Mancini et al. 2017;Grayson et al. 2017;Liu et al. 2020;Yang et al. 2021). In previous work, we have shown that Mn or protoporphyrin IX cofactors bound to de novo proteins can dock on the periplasmic surface of the reaction center and reduce the oxidized bacteriochlorophyll dimer, P + (Olson et al. 2016Espiritu et al. 2020;Allen et al. 2022). In this study, we utilize a hybrid fusion framework with a de novo protein genetically fused to the reaction center to investigate the potential for new electron transfer reactions. ...

... For the first time it was possible to assign ENDOR lines unambiguously to the individual dimer halves of the primary donor cation. This work on the electronic structure of the primary donor in bacterial photosynthesis formed the basis for a large number of further studies on this species; see for example [66][67][68][69][70][71][72]. It has been discussed that such an asymmetry in the electronic structure of P Áþ 865 might represent an important functional factor in controlling the vectorial properties of photosynthetic electron transfer to achieve a high quantum yield. ...

... Comparison of the structures of the paired chromophores in the purple bacterial reaction center and allophycocyanin, respectively, would at first glance suggest that the two systems should exhibit very different excitation energy transfer dynamics. The BChls in P are nearly in van der Waals contact with each other (Deisenhofer et al. 1984;Komiya et al. 1988), whereas the bilins in allophycocyanin are ∼10-12 Å apart for the nearest pyrrole rings and ∼ 20 Å center to center (Brejc et al. 1995). Nevertheless, the exciton internal conversion processes in the two systems apparently occur on the same timescale, ∼30 fs. ...

... Furthermore, studies of the interaction of RC with electrodes are a good model for the analysis of mechanisms of interprotein electron transfer (ET) (Haas et al., 2001; Jeuken, 2003; Khoshtariya et al., 2003; Willner et al., 1999). The advantages of using RCs from purple non-sulfur bacteria for electrode functionalization are in their simplicity since their molecular structure is well determined by X-ray crystallography (Allen et al., 1987; Deisenhofer et al., 1985; Lancaster and Michel, 1999) and they have a broad spectral sensitivity (from UV to near IR). These RCs are composed of three polypeptides H, L, and M. The polypeptides L and M, each forming five transmembrane -helices, are arranged in two-fold symmetry, whereas the H polypeptide is located at the cytoplasmic surface and binds to both L and M. A dimer of bacteriochlorophylls, so called the primary donor (P), two monomer bacteriochlorophylls (B A and B B ), two bacteriopheophytins (H A and H B ), two quinones (Q A and Q B ) and one iron are all non-covalently The orientation of RC on a Ni–NTA SAM. ...

... The PSI structural models (9,10) clearly identify the ET cofactors, which are organized into two symmetric chains with respect to the pseudo-C 2 symmetry axis parallel to the membrane plane. This is a common structural feature of all photosynthetic RCs whose structure is known (i.e., the purple bacterial RC (11,12), PSI (9,10), and PSII (13,14)). The photochem- ical and redox active cofactors are principally coordinated by the RC subunits PsaA and PsaB, which form a trans- membrane heterodimer. ...

... To date, only two principle architectural types are known that are suitable for this anisotropic environment: α-helical bundles and β-barrels (Figure 3) (von Heijne, 1994; 1996). Insights into these structures have been attained using electron microscopy and X-ray crystallography (Henderson and Unwin, 1975; Allen et al., 1988; Caffrey, 2003). However, high-resolution structure determination for membrane proteins remains a tedious and difficult task (Lacapère et al., 2007). ...

... Many efforts have been made to understand this nearunity quantum efficiency. X-ray crystal structures show that light-powered charge separation is accomplished by (bacterio) chlorin cofactors embedded in a protein matrix that spans the photosynthetic membrane (Feher et al. 1989). In the RC of the purple bacterium Rhodobacter (Rba.) ...

... For the first time it was possible to assign ENDOR lines unambiguously to the individual dimer halves of the primary donor "special pair". This work on the electronic structure of the primary donor formed the basis for a large number of further studies on this species, see for example [133,[190][191][192][193][194][195][196], leading to a deeper understanding of the role of the dimer in biological electron transfer [133,197,198]. Subsequently, similar ENDOR studies were performed on the primary donors, + 700 P  and + 680 P  , in the reaction centers of oxygenic photosynthesis, PS I and PS II [199][200][201][202]. ...

... Accordingly, many laboratories studied and reported the different aspects of photosynthesis in purple bacteria R. capsulatus, R. sphaeroides, R. palustris, Bradyrhizobium and R. gelatinosus (Allen et al., 1988;Bauer et al., 1993;Lang & Hunter, 1994). ...