Bacterial Cell Structure, Genomics And Gene Expression Flashcards
what is supercoiling
tight winding of genome to fit in the cell. can involve histone-like proteins
what enzymes recoil supercoils
DNA gyrase for +ve supercoils and DNA topoisomerase for -ve supercoils
what is genotypic gene control
amplification or rearrangement of genes
what is phenotypic gene control
occurs at transcription level and affects the RNA product and translation, altering the protein product
what do transmembrane sensors do
sensors detect the external environment and regulators regulate transcription accordingly
what is the difference between regulators and global regulators
regulators are specific to one operon, global sensors affect numerous operons around the cell by producing soluble regulators which can diffuse
what is the receptor response to antibiotics
sensors can detect antibiotics which results in the production of antibiotic- degrading enzyme beta lactamase
what was the first receptor discovered
flagellar chemotaxis- a CheA kinase protein and CheY regulator
what are the common receptor types identified
flagellar chemotaxis, osmolarity sensing, oxygen sensing and sporulation regulation
what is the role of microarray
the intensity of colour on the microarray depicts how much the gene is expressed
what are the two methods of determining the amount of gene expression
microarray and RNA sequencing with PCR- this is also able to identify promoter/ transcription start sites
what is the structure of a two- component regulator
a membrane- associated sensor and a cytoplasmic receptor
what is first to be phosphorylated
histodine (H) region of the sensor is phosphorylated from ATP which it then donates
where does the sensor donate its phosphate
histiding (H) on the sensor donates to the DD region of the regulator, which is then donated to the central D region
is phosphorylation of receptors irreverible
not always, some sensors can remove phosphate from the regulator after the stimulus event
