Persistence is a prime example of phenotypic heterogeneity, where a microbial population splits into two distinct subpopulations with different growth and survival properties as a result of reversible phenotype switching. Specifically, persister cells grow more slowly than normal cells under unstressed growth conditions, but survive longer under stress conditions such as the treatment with bact...

Despite their evolutionary significance, little is known about the adaptation dynamics of genomically rewired cells in evolution. We have confronted yeast cells carrying a rewired regulatory circuit with a severe and unforeseen challenge. The essential HIS3 gene from the histidine biosynthesis pathway was placed under the exclusive regulation of the galactose utilization system. Glucose contain...

Background: A routine phenotypic test has not been recommended for detection of metallo-β-lactamases (MBLs) producing Enterobacteriaceae species such as Escherichia coli. The current study was conducted to compare the 2-Mercaptopropionic acid (2-MPA) phenotypic method and ertapenem non-susceptibility test with polymerase chain reaction in predicting the production of MBLs in clinical isolates o...

b ackground : one of the main mechanisms of resistance to carbapenems is potential of klebsiella pneumoniae to produce k . pneumoniae carbapenemase (kpc). kpc is an important type of carbapenemase, which can hydrolyze carbapenems and other beta-lactam antibiotics. modified hodge test (mht) and  use  of  boronic  acid  as  a  kpc  inhibitor  are  two  types  of  phenotypic methods, which are use...

Temperature-sensitive periods were determined by application of temperature shifts and shocks to 3 temperature-sensitive cell division arrest (cda) mutants of Tetrahymena thermophila. A restrictive temperature, 36 degrees C, was found at which all 3 mutants are fully penetrant, yet other physiological effects are minimal. At this temperature, the temperature-sensitive period of cdaC2 is a uniqu...

For the first time in Iran 40 strains of Bifidobacterium were isolated from feces of Iranian subjects. By using phenotypic tests, 18 isolates were identified as Bifidobacterium longum, 10 as Bifidobacterium bifidum and one as Bifidobacterium catenolatum. In order to validate these results and also to identify other isolates that had not been identified by phenotypic tests, two methods of PCR wi...

methicillin-resistant staphylococcus aureus (mrsa) is the main cause of hospital infection emerged over the last decades. rapid detection of mrsa is important for patient care and proper usage of infection control. detection of meca genes (encoding resistance to methicillin and other similar antibiotics) and nuc genes (encoding staphylococcal thermostable nuclease) by pcr method is now consider...