Regulation of constant cell elongation and Sfm pili synthesis in Escherichia coli via two active forms of FimZ orphan response regulator.

Escherichia coli (E. coli) has multiple copies of the chaperone-usher (CU) pili operon in five fimbria groups: CU pili, curli, type IV pili, type III secretion pili, and type IV secretion pili. Commensal E.

Epistatic Effect of Regulators to the Adaptive Growth of Escherichia coli.

Bacteria survive in the environment with three steps: a sensing environmental conditions, a responding to sensed signals, and an adaptation for proper survival in the environment. An adapting bacterial cell occurs cell division to increase the number of sister cells, termed adaptive growth. Two-component systems (TCSs), representing the main bacterial signal transduction systems, consist of a pair of one sensor kinase (SK) and one response regulator (RR), and RR genes are abundant in most bacterial genomes as part of the core genome.

Measurement of the Promoter Activity in by Using a Luciferase Reporter.

The reporter system is widely used technique for measuring promoter activity in bacterial cells. Until now, a number of reporter system have been developed, but the bioluminescent reporter constructed from the bacterial luciferase genes is one of the useful systems for measuring dynamics of gene expression. The introduced bioluciferase reporter enables easy, fast, and sensitive measurement of the promoter activity without cell lysis because the substrates of bioluminescent reaction are synthesized inside the bacterial cell, thereby allowing low-cost experiments.

Regulatory roles of pyruvate-sensing two-component system PyrSR (YpdAB) in Escherichia coli K-12.

When the rate of production of metabolites in bacteria exceeds the amounts needed for cell growth, excess metabolites are secreted into the extracellular environment. Upon entry into poor nutrient conditions, overflowed exometabolites are reused to continue cell growth and survival. At present, however, the genetic system for utilization of exometabolites is poorly understood even for the best-characterized model prokaryote Escherichia coli.

Influenza virus replication raises the temperature of cells.

Influenza virus invades the cell by binding sialic acid on the cell membrane through haemagglutinin (HA), and then genome replication and transcription are carried out in the nucleus to produce progeny virus. Multiplication of influenza virus requires metabolites, such as nucleotides and amino acids, as well as cellular machinery to synthesize its genome and proteins, thereby producing viral particles. Influenza virus infection forces the start of several metabolic systems in the cell, which consume or generate large amounts of energy.

Influenza Virus Infection Induces Host Pyruvate Kinase M Which Interacts with Viral RNA-Dependent RNA Polymerase.

Influenza virus RNA-dependent RNA polymerase (RdRp) is a heterotrimer of three viral proteins, PB1, PB2, and PA and is involved in both transcription and replication of the negative strand of the viral RNA (vRNA) genome. RdRp is multifunctional, possessing RNA polymerase, cap binding, and endonuclease activities. The enzyme synthesizes three different RNAs, complementary RNA (cRNA) and messenger RNA (mRNA) from vRNA, and vRNA from cRNA.

Analysis of the Changes in Expression Levels of Sialic Acid on Influenza-Virus-Infected Cells Using Lectin-Tagged Polymeric Nanoparticles.

Viral infections affect millions around the world, sometimes leading to severe consequences or even epidemics. Understanding the molecular dynamics during viral infections would provide crucial information for preventing or stopping the progress of infections. However, the current methods often involve the disruption of the infected cells or expensive and time-consuming procedures.

Cardiac output and other hemodynamic variables in anesthetized dogs undergoing laparotomy because of abdominal neoplasia.

Objective: To measure cardiac output and other hemodynamic variables in anesthetized dogs undergoing laparotomy because of abdominal neoplasia.

Design: Prospective case series.

Animals: 8 dogs with splenic or hepatic tumors.

Heterotopic implantation of a porcine bioprosthetic heart valve in a dog with aortic valve endocarditis.

Case Description: A 5-year-old male German Shepherd Dog was evaluated because of a 5-month history of progressive lethargy, weight loss, and heart failure.

Clinical Findings: On physical examination, bounding femoral pulses and systolic and diastolic murmurs were detected. Echocardiography revealed severe aortic valve insufficiency (AVI) and a large vegetative lesion on the aortic valve consistent with aortic valve endocarditis.

Evaluation of hemodynamic measurements, including lithium dilution cardiac output, in anesthetized dogs undergoing ovariohysterectomy.

Objective: To measure cardiac output in healthy female anesthetized dogs by use of lithium dilution cardiac output and determine whether changes in mean arterial pressure were caused by changes in cardiac output or systemic vascular resistance.

Design: Prospective clinical study.

Animals: 20 healthy female dogs.