Biochemical Properties and Biological Functions of Atp-Dependent Proteases In Bacterial Cells

ABSTRACT Calpain 3 is a nonlysosomal cysteine protease whose biological functions remain unknown. We previously demonstrated that this protease is altered in limb girdle muscular dystrophy type 2A patients. Preliminary observations suggested that its gene is subjected to alternative splicing. In this paper, we characterize transcriptional and posttranscriptional events leading to alterations involving the NS, IS1, and IS2 regions and/or the calcium binding domains of the mouse calpain 3 gene (capn3). These events can be divided into three groups: (i) splicing of exons that preserve the translation frame, (ii) inclusion of two distinct intronic sequences between exons 16 and 17 that disrupt the frame and would lead, if translated, to a truncated protein lacking domain IV, and (iii) use of an alternative first exon specific to lens tissue. In addition, expression of these isoforms seems to be regulated. Investigation of the proteolytic activities and titin binding abilities of the translation products of some of these isoforms clearly indicated that removal of these different protein segments affects differentially the biochemical properties examined. In particular, removal of exon 6 impaired the autolytic but not fodrinolytic activity and loss of exon 16 led to an increased titin binding and a loss of fodrinolytic activity. These results are likely to impact our understanding of the pathophysiology of calpainopathies and the development of therapeutic strategies.

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ATP synthase from bovine heart mitochondria: reconstitution into unilamellar phospholipid vesicles of the pure enzyme in a functional state

Biochemical Journal ◽

10.1042/bj3180351 ◽

1996 ◽

Vol 318 (1) ◽

pp. 351-357 ◽

Cited By ~ 29

Author(s):

Georg GROTH ◽

John E. WALKER

Keyword(s):

Atp Hydrolysis ◽

Three Dimensional ◽

Biochemical Properties ◽

Proton Gradient ◽

Heart Mitochondria ◽

Phospholipid Vesicles ◽

Dependent Manner ◽

Biological Functions ◽

Bovine Heart ◽

F1fo Atpase

A highly purified and monodisperse preparation of proton-translocating F1Fo-ATPase from bovine heart mitochondria is an assembly of 16 unlike polypeptides. This preparation has been reconstituted in the presence of various detergents into unilamellar phospholipid vesicles. Incorporation of the enzyme into vesicles increases the ATP hydrolase activity of the enzyme by 10–20-fold, depending on the detergent, and the highest activities of ATP hydrolysis, 70 units/mg, were obtained by reconstitution from dodecylmaltoside or CHAPS. This activity is mostly sensitive to inhibitors that act on the Fo membrane sector of the complex. From the quenching of the pH-sensitive probe, 9-amino-6-chloro-2-methoxyacridine, it was shown that the reconstituted enzyme was able to form a transmembrane proton gradient in an ATP-dependent manner. By co-reconstitution of the enzyme with bacteriorhodopsin, it was demonstrated that in the presence of a light-induced proton gradient the enzyme can synthesize ATP from ADP and phosphate. Therefore, the characteristic biological functions of the F1Fo-ATPase in mitochondria have been demonstrated with the purified enzyme. Thus, in terms of both its physical and biochemical properties, the purified enzyme fulfils important pre-requisites for formation of two- and three-dimensional crystals.

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Protective Effect and Potential Antioxidant Role of Kakadu Plum Extracts on Alcohol-Induced Oxidative Damage in HepG2 Cells

Applied Sciences ◽

10.3390/app12010236 ◽

2021 ◽

Vol 12 (1) ◽

pp. 236

Author(s):

Reshmi Akter ◽

Gi-Young Kwak ◽

Jong Chan Ahn ◽

Ramya Mathiyalagan ◽

Zelika Mega Ramadhania ◽

...

Keyword(s):

Vitamin C ◽

High Performance ◽

Chemical Constituents ◽

Biochemical Properties ◽

Ros Generation ◽

Biological Functions ◽

Human Hepatoma Cells ◽

Commercially Important ◽

Kakadu Plum

Serial alcohol consumption causes alcoholic liver disease (ALD), which can lead to fatty liver, hepatitis, and cirrhosis. Terminalia ferdinandiana (Kakadu plum) is an indigenous fruit of Australia, which is utilized as a functional food. It is a commercially important antioxidant as it contains a more eloquent level of ascorbic acid than other oranges. In this study, we analyzed the chemical constituents of vitamin C, gallic acid, ellagic acid, and daidzin via High-performance liquid chromatography (HPLC) in the Kakadu plum from two different regions including the Northern Territory (NT) and Western Australia (WA), and compared their biochemical properties. The vitamin C content was much higher (almost 70%) in Kakadu plum (KKD) from the NT than WA. Moreover, ROS generation was inhibited significantly in HepG2 (human hepatoma) cells with the KKD-NT extract treatment when compared to the KKD-WA extract treatment. The cytotoxicity produced by ethanol was significantly suppressed in response to the treatment with both of the samples. In addition, our samples (KKD-NT and KKD-WA) increased the activity of two key enzymes involving alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) that metabolize ethanol. These results show the biochemical confirmation of the mechanism by which KKD exhibits its biological functions including relief from alcohol hangovers as well as protection of the liver cells by the suppression of ROS production and toxic insults.

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EVI1 in Leukemia and Solid Tumors

Cancers ◽

10.3390/cancers12092667 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2667

Author(s):

Beiyuan Liang ◽

Jing Wang

Keyword(s):

Solid Tumors ◽

Transcriptional Activation ◽

Myeloid Leukemia ◽

Chromosomal Rearrangements ◽

Biochemical Properties ◽

Chromosomal Translocations ◽

Biological Functions ◽

Transcription Activator ◽

Myeloid Leukemias ◽

Genetic Structures

The EVI1 gene encodes for a transcription factor with two zinc finger domains and is transcriptionally activated in a subset of myeloid leukemias. In leukemia, the transcriptional activation of EVI1 usually results from chromosomal rearrangements. Besides leukemia, EVI1 has also been linked to solid tumors including breast cancer, lung cancer, ovarian cancer and colon cancer. The MDS1/EVI1 gene is encoded by the same locus as EVI1. While EVI1 functions as a transcription repressor, MDS1/EVI1 acts as a transcription activator. The fusion protein encoded by the AML1/MDS1/EVI1 chimeric gene, resulting from chromosomal translocations in a subset of chronic myeloid leukemia, exhibits a similar function to EVI1. EVI1 has been shown to regulate cell proliferation, differentiation and apoptosis, whereas the functions of MDS1/EVI1 and AML1/MDS1/EVI1 remain elusive. In this review, we summarize the genetic structures, biochemical properties and biological functions of these proteins in cancer.

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SAG/ROC/Rbx/Hrt, a Zinc RING Finger Gene Family: Molecular Cloning, Biochemical Properties, and Biological Functions

Antioxidants and Redox Signaling ◽

10.1089/15230860152542989 ◽

2001 ◽

Vol 3 (4) ◽

pp. 635-650 ◽

Cited By ~ 59

Author(s):

Yi Sun ◽

Mingjia Tan ◽

Hangjun Duan ◽

Manju Swaroop

Keyword(s):

Gene Family ◽

Molecular Cloning ◽

Ring Finger ◽

Biochemical Properties ◽

Biological Functions

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PA28γ: New Insights on an Ancient Proteasome Activator

Biomolecules ◽

10.3390/biom11020228 ◽

2021 ◽

Vol 11 (2) ◽

pp. 228 ◽

Cited By ~ 1

Author(s):

Paolo Cascio

Keyword(s):

Molecular Mechanisms ◽

Regulatory Protein ◽

Biological Properties ◽

Biochemical Properties ◽

20S Proteasome ◽

Biological Functions ◽

Cellular Processes ◽

Degradation Rates ◽

The Common ◽

Proteasome Regulators

PA28 (also known as 11S, REG or PSME) is a family of proteasome regulators whose members are widely present in many of the eukaryotic supergroups. In jawed vertebrates they are represented by three paralogs, PA28α, PA28β, and PA28γ, which assemble as heptameric hetero (PA28αβ) or homo (PA28γ) rings on one or both extremities of the 20S proteasome cylindrical structure. While they share high sequence and structural similarities, the three isoforms significantly differ in terms of their biochemical and biological properties. In fact, PA28α and PA28β seem to have appeared more recently and to have evolved very rapidly to perform new functions that are specifically aimed at optimizing the process of MHC class I antigen presentation. In line with this, PA28αβ favors release of peptide products by proteasomes and is particularly suited to support adaptive immune responses without, however, affecting hydrolysis rates of protein substrates. On the contrary, PA28γ seems to be a slow-evolving gene that is most similar to the common ancestor of the PA28 activators family, and very likely retains its original functions. Notably, PA28γ has a prevalent nuclear localization and is involved in the regulation of several essential cellular processes including cell growth and proliferation, apoptosis, chromatin structure and organization, and response to DNA damage. In striking contrast with the activity of PA28αβ, most of these diverse biological functions of PA28γ seem to depend on its ability to markedly enhance degradation rates of regulatory protein by 20S proteasome. The present review will focus on the molecular mechanisms and biochemical properties of PA28γ, which are likely to account for its various and complex biological functions and highlight the common features with the PA28αβ paralog.

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Obtaining a fluorescently labeled endophytic strain of bacteria Herbaspirillum lusitanum P6-12 for their detection in vivo and in vitro

Izvestiya of Saratov University New Series Series Chemistry Biology Ecology ◽

10.18500/1816-9775-2021-21-3-286-291 ◽

2021 ◽

Vol 21 (3) ◽

pp. 286-291

Author(s):

Arapat Rustamovna Bagavova ◽

◽

Natal’ya S. Velichko ◽

Timofey E. Pylayev ◽

Yuliya P. Fedonenko ◽

...

Keyword(s):

Recombinant Strain ◽

Fluorescent Protein ◽

Biochemical Properties ◽

Growth Media ◽

Bacterial Cells ◽

Vector Plasmid ◽

Green Fluorescent ◽

Model Strain

The Herbaspirillum lusitanum P6-12 strain containing the vector plasmid pJN105TurboGFP, which encodes the synthesis of the green fluorescent protein GFP, and which has resistance to the antibiotic gentamicin, was obtained by electroporation. The constructed strain of H. lusitanum P6-12 in cultural, morphological and biochemical properties did not differ from the original typical natural strain of H. lusitanum P6-12. On solid growth media, the recombinant strain formed yellow-green colonies, fluorescent under UV irradiation. Upon inoculation with the resulting culture of plant objects, a green glow of the marked H. lusitanum P6-12 cells, actively colonizing the internal tissues of the host plant, was observed. The created strain can be used as a model strain for studying the patterns and characteristics of the behaviour of organisms in integrated systems, including for tracking bacterial cells during interaction with plants, assessing their survival, competitiveness, etc.

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Septin functions in organ system physiology and pathology

Biological Chemistry ◽

10.1515/hsz-2013-0233 ◽

2014 ◽

Vol 395 (2) ◽

pp. 123-141 ◽

Cited By ~ 75

Author(s):

Lee Dolat ◽

Qicong Hu ◽

Elias T. Spiliotis

Keyword(s):

Biochemical Properties ◽

Organ System ◽

Protein Isoforms ◽

Biological Functions ◽

Tissue Specific ◽

Gtp Binding ◽

Organ Systems ◽

System Physiology ◽

And Function ◽

Made In

Abstract Human septins comprise a family of 13 genes that encode for >30 protein isoforms with ubiquitous and tissue-specific expressions. Septins are GTP-binding proteins that assemble into higher-order oligomers and filamentous polymers, which associate with cell membranes and the cytoskeleton. In the last decade, much progress has been made in understanding the biochemical properties and cell biological functions of septins. In parallel, a growing number of studies show that septins play important roles for the development and physiology of specific tissues and organs. Here, we review the expression and function of septins in the cardiovascular, immune, nervous, urinary, digestive, respiratory, endocrine, reproductive, and integumentary organ systems. Furthermore, we discuss how the tissue-specific functions of septins relate to the pathology of human diseases that arise from aberrations in septin expression.

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