Specific mutation near the primary donor in photosystem I from Chlamydomonas reinhardtii alters the trapping time and spectroscopic properties of P700

Alexander N. Melkozernov, Hui Su, Su Lin, Scott Bingham, Andrew Webber, Robert E. Blankenship

Research output: Contribution to journalArticle

32 Citations (Scopus)

Abstract

Time-resolved absorption and fluorescence spectroscopy were used to investigate the energy and electron transfer processes in the detergent- isolated photosystem I core particles from the site-directed mutant of Chlamydomonas reinhardtii with the histidine-656 of PsaB replaced by asparagine [HN(B656) mutation]. The specific mutation near the primary donor molecule results in a 40 mV increase in the P700/P700 + midpoint potential [Webber, A. N., Su Hui, Bingham, S. E., Kass, H., Krabben, L., Kuhn, M., Jordan, R., Schlodder, E., and Lubitz, W. (1996) Biochemistry 35, 12857-12863]. There is no indication that the HN(B656) mutation affects the spectral distribution of the antenna pigments. However, the lifetime of the trapping process measured independently by transient absorption and fluorescence spectroscopy in the mutant PSI core antenna is increased by a factor of approximately 2 (~65 ps compared to ~30 ps in the wild-type PSI). This implies that the trapping process in the PSI antenna is limited by the process where the primary donor molecule directly participates. The HN(B656) mutation results in the appearance of a new bleaching band at 670 nm in the spectrum which is due to formation of P700 + upon photooxidation. The difference spectrum of the photoreduction of the possible primary acceptor, A0 in the mutant PSI is very similar to wild type, indicating that it is unaffected by the HN(B656) mutation. Possible mechanisms for slowing of the trapping process and the appearance of a new band in the P700 - P700 + difference spectrum of the HN(B656) PSI are discussed.

Original languageEnglish (US)
Pages (from-to)2898-2907
Number of pages10
JournalBiochemistry
Volume36
Issue number10
DOIs
StatePublished - Mar 11 1997

Fingerprint

Photosystem I Protein Complex
Chlamydomonas reinhardtii
Fluorescence spectroscopy
Antennas
Absorption spectroscopy
Mutation
Fluorescence Spectrometry
Biochemistry
Molecules
Photooxidation
Asparagine
Bleaching
Histidine
Pigments
Detergents
Energy Transfer
Electrons

ASJC Scopus subject areas

  • Biochemistry

Cite this

Specific mutation near the primary donor in photosystem I from Chlamydomonas reinhardtii alters the trapping time and spectroscopic properties of P700 . / Melkozernov, Alexander N.; Su, Hui; Lin, Su; Bingham, Scott; Webber, Andrew; Blankenship, Robert E.

In: Biochemistry, Vol. 36, No. 10, 11.03.1997, p. 2898-2907.

Research output: Contribution to journalArticle

@article{019a8065756b48509f416b2d162c63d9,
title = "Specific mutation near the primary donor in photosystem I from Chlamydomonas reinhardtii alters the trapping time and spectroscopic properties of P700",
abstract = "Time-resolved absorption and fluorescence spectroscopy were used to investigate the energy and electron transfer processes in the detergent- isolated photosystem I core particles from the site-directed mutant of Chlamydomonas reinhardtii with the histidine-656 of PsaB replaced by asparagine [HN(B656) mutation]. The specific mutation near the primary donor molecule results in a 40 mV increase in the P700/P700 + midpoint potential [Webber, A. N., Su Hui, Bingham, S. E., Kass, H., Krabben, L., Kuhn, M., Jordan, R., Schlodder, E., and Lubitz, W. (1996) Biochemistry 35, 12857-12863]. There is no indication that the HN(B656) mutation affects the spectral distribution of the antenna pigments. However, the lifetime of the trapping process measured independently by transient absorption and fluorescence spectroscopy in the mutant PSI core antenna is increased by a factor of approximately 2 (~65 ps compared to ~30 ps in the wild-type PSI). This implies that the trapping process in the PSI antenna is limited by the process where the primary donor molecule directly participates. The HN(B656) mutation results in the appearance of a new bleaching band at 670 nm in the spectrum which is due to formation of P700 + upon photooxidation. The difference spectrum of the photoreduction of the possible primary acceptor, A0 in the mutant PSI is very similar to wild type, indicating that it is unaffected by the HN(B656) mutation. Possible mechanisms for slowing of the trapping process and the appearance of a new band in the P700 - P700 + difference spectrum of the HN(B656) PSI are discussed.",
author = "Melkozernov, {Alexander N.} and Hui Su and Su Lin and Scott Bingham and Andrew Webber and Blankenship, {Robert E.}",
year = "1997",
month = "3",
day = "11",
doi = "10.1021/bi962235m",
language = "English (US)",
volume = "36",
pages = "2898--2907",
journal = "Biochemistry",
issn = "0006-2960",
publisher = "American Chemical Society",
number = "10",

}

TY - JOUR

T1 - Specific mutation near the primary donor in photosystem I from Chlamydomonas reinhardtii alters the trapping time and spectroscopic properties of P700

AU - Melkozernov, Alexander N.

AU - Su, Hui

AU - Lin, Su

AU - Bingham, Scott

AU - Webber, Andrew

AU - Blankenship, Robert E.

PY - 1997/3/11

Y1 - 1997/3/11

N2 - Time-resolved absorption and fluorescence spectroscopy were used to investigate the energy and electron transfer processes in the detergent- isolated photosystem I core particles from the site-directed mutant of Chlamydomonas reinhardtii with the histidine-656 of PsaB replaced by asparagine [HN(B656) mutation]. The specific mutation near the primary donor molecule results in a 40 mV increase in the P700/P700 + midpoint potential [Webber, A. N., Su Hui, Bingham, S. E., Kass, H., Krabben, L., Kuhn, M., Jordan, R., Schlodder, E., and Lubitz, W. (1996) Biochemistry 35, 12857-12863]. There is no indication that the HN(B656) mutation affects the spectral distribution of the antenna pigments. However, the lifetime of the trapping process measured independently by transient absorption and fluorescence spectroscopy in the mutant PSI core antenna is increased by a factor of approximately 2 (~65 ps compared to ~30 ps in the wild-type PSI). This implies that the trapping process in the PSI antenna is limited by the process where the primary donor molecule directly participates. The HN(B656) mutation results in the appearance of a new bleaching band at 670 nm in the spectrum which is due to formation of P700 + upon photooxidation. The difference spectrum of the photoreduction of the possible primary acceptor, A0 in the mutant PSI is very similar to wild type, indicating that it is unaffected by the HN(B656) mutation. Possible mechanisms for slowing of the trapping process and the appearance of a new band in the P700 - P700 + difference spectrum of the HN(B656) PSI are discussed.

AB - Time-resolved absorption and fluorescence spectroscopy were used to investigate the energy and electron transfer processes in the detergent- isolated photosystem I core particles from the site-directed mutant of Chlamydomonas reinhardtii with the histidine-656 of PsaB replaced by asparagine [HN(B656) mutation]. The specific mutation near the primary donor molecule results in a 40 mV increase in the P700/P700 + midpoint potential [Webber, A. N., Su Hui, Bingham, S. E., Kass, H., Krabben, L., Kuhn, M., Jordan, R., Schlodder, E., and Lubitz, W. (1996) Biochemistry 35, 12857-12863]. There is no indication that the HN(B656) mutation affects the spectral distribution of the antenna pigments. However, the lifetime of the trapping process measured independently by transient absorption and fluorescence spectroscopy in the mutant PSI core antenna is increased by a factor of approximately 2 (~65 ps compared to ~30 ps in the wild-type PSI). This implies that the trapping process in the PSI antenna is limited by the process where the primary donor molecule directly participates. The HN(B656) mutation results in the appearance of a new bleaching band at 670 nm in the spectrum which is due to formation of P700 + upon photooxidation. The difference spectrum of the photoreduction of the possible primary acceptor, A0 in the mutant PSI is very similar to wild type, indicating that it is unaffected by the HN(B656) mutation. Possible mechanisms for slowing of the trapping process and the appearance of a new band in the P700 - P700 + difference spectrum of the HN(B656) PSI are discussed.

UR - http://www.scopus.com/inward/record.url?scp=0030887653&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030887653&partnerID=8YFLogxK

U2 - 10.1021/bi962235m

DO - 10.1021/bi962235m

M3 - Article

C2 - 9062119

AN - SCOPUS:0030887653

VL - 36

SP - 2898

EP - 2907

JO - Biochemistry

JF - Biochemistry

SN - 0006-2960

IS - 10

ER -