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F F Litvin

Publications and source records attributed to F F Litvin.

At least 55 records · Page 3Linked to original sources
PubMedDate not supplied

[New intermediates in the photochemical transformation of rhodopsin].

The conditions of preferential accumulation of intermediates of the photochemical reaction cycle of bacteriorhodopsin (BR) P550 and P419 at low temperature are found. Upon illumination P550 and P419 undergo photochemical conversions into the light-adapted form of BR (P570), forming during this conversions a number of new intermediates: P550 leads to P560-- -- -- leads to P570; P419 leads to P421-- -- -- leads to P565-- -- -- leads to P585-- -- -- leads to P570; P419 leads to P470-- -- -- leads to P570. All intermediates are photoactive. All light reactions are photoreversible and give formation to the products with absorption maximum shifted to the red as compared to the initial state. The absorption spectra of intermediates are complex and include several bands which are more pronounced in the spectrum of P419 (maxima at 442, 419, 398 nm, a shoulder at 375 nm) and P421, less in the spectrum of P570 (maximum at 578 nm, shoulders at 540 and 608 nm) and others.

Bacteriorhodopsins↗
PubMedDate not supplied

[Resolution of the fluorescence and absorption spectra of chlorophyll a in the cell into its components].

The total number, band widths, absorption and fluorescence peak positions of universal forms of chlorophyll a in vivo were identified by means of computer curve analysis, Stepanov's relation and low temperature derivative spectroscopy. The identified pigment forms are as follows: Chl669(661), Chl676(674), Chl686(680), Chl691(687), Chl697(691), Chl706(698), Chl715(702) Chl726(709), Chl738(715) and Chl750--755(720--724) (the lower index--absorption peak position, the upper one--fluorescence peak position). The O--O electronic transitions vibronic bands energy one of the forms of chlorphyll alpha enumerated above changes for constant equal 140 cm--1.

Chemical Phenomena↗