Advertisement

Topics

Mechanism of opening a sliding clamp.

08:00 EDT 29th September 2017 | BioPortfolio

Summary of "Mechanism of opening a sliding clamp."

Clamp loaders load ring-shaped sliding clamps onto DNA where the clamps serve as processivity factors for DNA polymerases. In the first stage of clamp loading, clamp loaders bind and stabilize clamps in an open conformation, and in the second stage, clamp loaders place the open clamps around DNA so that the clamps encircle DNA. Here, the mechanism of the initial clamp opening stage is investigated. Mutations were introduced into the Escherichia coli β-sliding clamp that destabilize the dimer interface to determine whether the formation of an open clamp loader-clamp complex is dependent on spontaneous clamp opening events. In other work, we showed that mutation of a positively charged Arg residue at the β-dimer interface and high NaCl concentrations destabilize the clamp, but neither facilitates the formation of an open clamp loader-clamp complex in experiments presented here. Clamp opening reactions could be fit to a minimal three-step 'bind-open-lock' model in which the clamp loader binds a closed clamp, the clamp opens, and subsequent conformational rearrangements 'lock' the clamp loader-clamp complex in a stable open conformation. Our results support a model in which the E. coli clamp loader actively opens the β-sliding clamp.

Affiliation

Journal Details

This article was published in the following journal.

Name: Nucleic acids research
ISSN: 1362-4962
Pages: 10178-10189

Links

DeepDyve research library

PubMed Articles [6377 Associated PubMed Articles listed on BioPortfolio]

Crystal structures and biochemical characterization of DNA sliding clamps from three Gram-negative bacterial pathogens.

Bacterial sliding clamps bind to DNA and act as protein-protein interaction hubs for several proteins involved in DNA replication and repair. The partner proteins all bind to a common pocket on slidin...

p15PAF binding to PCNA modulates the DNA sliding surface.

p15PAF is an oncogenic intrinsically disordered protein that regulates DNA replication and lesion bypass by interacting with the human sliding clamp PCNA. In the absence of DNA, p15PAF traverses the P...

RNA Polymerase Clamp Movement Aids Dissociation from DNA but Is Not Required for RNA Release at Intrinsic Terminators.

In bacteria, disassembly of elongating transcription complexes (ECs) can occur at intrinsic terminators in a 2-3 nucleotide window after transcription of multiple kilobase pairs of DNA. Intrinsic term...

Comparing Off-Clamp and On-Clamp Robot-Assisted Partial Nephrectomy: A Prospective Randomized Trial.

To determine whether performing robot-assisted partial nephrectomy without warm ischemia "off-clamp" results in favorable postoperative renal functional outcomes compared with the on-clamp method.

T4 DNA ligase structure reveals a prototypical ATP-dependent ligase with a unique mode of sliding clamp interaction.

DNA ligases play essential roles in DNA replication and repair. Bacteriophage T4 DNA ligase is the first ATP-dependent ligase enzyme to be discovered and is widely used in molecular biology, but its s...

Clinical Trials [1650 Associated Clinical Trials listed on BioPortfolio]

Nail Versus Sliding Hip Screw for Trochanteric Hip Fractures

The investigators therefore propose to undertake a further randomised controlled trial comparing the sliding hip screw (SHS) with the Targon PFT intramedullary nail. The aim is to see if t...

InterTAN IM Nail Versus Sliding Hip Screw in Geriatric Fractures

Elderly patients with an intertrochanteric hip fracture will be randomized to receive either a sliding hip screw (SHS) (control group) or InterTAN intermedullary nail (IMN) (experimental ...

Mechanisms of Hypoglycemia Associated Autonomic Dysfunction, Q.3

It has been found that in some cases, when a person with Diabetes Mellitus has an episode of low blood sugar,or hypoglycemia, and then later exercises, he or she is vulnerable to another b...

Evaluation of Surgical Fixation Using Alternative Implants for the Treatment of Hip Fractures

The primary purpose of this study is to assess the impact of sliding hip screws versus cannulated screw fixation on rates of revision surgery at 2 years in individuals over 50 years of age...

Neurodynamic Study

Sciatica is a debilitating and costly condition. Prognostically, patients presenting with leg pain often have a poor recovery and some go onto have spinal surgery. However, in the absence ...

Medical and Biotech [MESH] Definitions

An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used.

A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.

STOMACH herniation located at or near the diaphragmatic opening for the ESOPHAGUS, esophageal hiatus. When the ESOPHAGOGASTRIC JUNCTION is above the DIAPHRAGM, it is called a SLIDING HIATAL HERNIA. When the ESOPHAGOGASTRIC JUNCTION is below the DIAPHRAGM, it is called a PARAESOPHAGEAL HIATAL HERNIA.

Surgical formation of an opening into the trachea through the neck, or the opening so created.

Surface resistance to the relative motion of one body against the rubbing, sliding, rolling, or flowing of another with which it is in contact.

Advertisement
Quick Search
Advertisement
Advertisement

 


DeepDyve research library

Relevant Topic

Bioinformatics
Bioinformatics is the application of computer software and hardware to the management of biological data to create useful information. Computers are used to gather, store, analyze and integrate biological and genetic information which can then be applied...


Searches Linking to this Article