An analytical technique for the in situ characterization of b- and c-type cytochromes has been developed. From evaluation of the results of potentiometric measurements and spectrum deconvolutions, it was concluded that an integrated best-fit analysis of potentiometric and spectral data gave the most reliable results. In the total cytochrome b content of cytoplasmic membranes from aerobically grown Escherichia coli, four major components are distinguished with alpha-band maxima at 77 K of 555.7, 556.7, 558.6 and 563.5 nm, and midpoint potentials at pH 7.0 of 46, 174, -75 and 187 mV, respectively. In addition, two very small contributions to the alpha-band spectrum at 547.0 and 560.2 nm, with midpoint potentials of 71 and 169 mV, respectively, have been distinguished. On the basis of their spectral properties they should be designated as a cytochrome c and a cytochrome b, respectively. In Complex III, isolated from beef heart mitochondria, five cytochromes are distinguished: cytochrome c1 (lambda m (25 degrees C) = 553.5 nm; E'0 = 238 mV) and four cytochromes b (lambda m (25 degrees C) = 558.6, 561.2, 562.1, 566.1 nm and E'0 = -83, 26, 85, -60 mV).

Download full-text PDF

Source
http://dx.doi.org/10.1016/0005-2728(82)90021-4DOI Listing

Publication Analysis

Top Keywords

situ characterization
8
characterization c-type
8
c-type cytochromes
8
escherichia coli
8
complex iii
8
beef heart
8
heart mitochondria
8
midpoint potentials
8
lambda degrees
8
method situ
4

Similar Publications

A sustainable biosorbent, silver nanoparticles-decorated coffee-ground waste (CWAg), was synthesized through a simple in-situ reduction method. CWAg is extensively characterized via SEM-EDX, PZC, FTIR, XRD, HR-TEM, and XPS analyses. The biosorbent was tested to remove chromium (Cr(VI)) and methylene blue (MB) from wastewater, and its antibacterial properties was evaluated.

View Article and Find Full Text PDF

Discovery and Characterization of a Metastable Cubic Interstitial Nickel-Carbon System with an Expanded Lattice.

ACS Nano

January 2025

Faculty III Process Sciences, Institute of Materials Science and Technology, Chair of Advanced Ceramic Materials, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany.

Metastable, , kinetically favored but thermodynamically not stable, interstitial solid solutions of carbon in iron are well-understood. Carbon can occupy the interstitial atoms of the host metal, altering its properties. Alloying of the host metal results in the stabilization of the FeC phases, widening its application.

View Article and Find Full Text PDF

Development of nucleus-targeted histone-tail-based photoaffinity probes to profile the epigenetic interactome in native cells.

Nat Commun

January 2025

School of Food and Biological Engineering, Engineering Research Center of Bio-process, Ministry of Education, Key Laboratory of Animal Source of Anhui Province, Hefei University of Technology, Hefei, 230009, China.

Dissection of the physiological interactomes of histone post-translational modifications (hPTMs) is crucial for understanding epigenetic regulatory pathways. Peptide- or protein-based histone photoaffinity tools expanded the ability to probe the epigenetic interactome, but in situ profiling in native cells remains challenging. Here, we develop a nucleus-targeting histone-tail-based photoaffinity probe capable of profiling the hPTM-mediated interactomes in native cells, by integrating cell-permeable and nuclear localization peptide modules into an hPTM peptide equipped with a photoreactive moiety.

View Article and Find Full Text PDF

[Characteristics of RET gene rearrangement detected by fluorescence in situ hybridization in lung cancer].

Zhonghua Bing Li Xue Za Zhi

January 2025

Department of Pathology, Peking Union Medical College Hospital, Peking Union Medical College,Chinese Academy of Medical Sciences, Beijing100730, China.

To investigate the characteristics of RET gene rearrangement revealed by fluorescence in situ hybridization (FISH) in lung cancer. A total of 616 formalin-fixed paraffin-embedded surgical samples from lung adenocarcinomas with wild-type EGFR gene and no ALK protein expression by immunohistochemistry obtained at Peking Union Medical College Hospital, Beijing, China between December 2019 and April 2022 were included. Thirty-three tumors with RET gene rearrangement determined by imbalanced-based reverse-transcription droplet digital PCR (RT-ddPCR) were analyzed using break-apart FISH.

View Article and Find Full Text PDF

Background: Immune checkpoint inhibitors targeting programmed cell death protein-1 (PD-1) are the first line of treatment for many solid tumors including melanoma. PD-1 blockade enhances the effector functions of melanoma-infiltrating CD8 T cells, leading to durable tumor remissions. However, 55% of patients with melanoma do not respond to treatment.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!