Disease relevance of helD

• Double helicase II (uvrD)-helicase IV (helD) deletion mutants are defective in the recombination pathways of Escherichia coli [1].

High impact information on helD

• Inhibition of the unwinding reaction was due to the presence of bound Lac repressor as evidenced by the substantially weaker inhibition of helicase IV by Lac repressor in the presence of IPTG [2].
• To probe for functional redundancy among these helicases, mutant strains containing single, double, and triple deletions in the helD, uvrD, and recQ genes were constructed and examined for conjugational recombination efficiency and DNA repair proficiency [3].
• Cell strains lacking helicase IV (delta helD) exhibited no increase in sensitivity to UV irradiation but were slightly more resistant to methyl methanesulfonate (MMS) than the isogenic wild-type cell strain [1].
• The Escherichia coli helD (encoding helicase IV) and uvrD (encoding helicase II) genes have been deleted, independently and in combination, from the chromosome and replaced with genes encoding antibiotic resistance [1].
• Other superfamily I helicases such as, UvrD/Rep/PcrA also possess these residues but in addition they interact with adenine via a conserved arginine, which is replaced by a serine in helicase IV [4].

Chemical compound and disease context of helD

• Rep protein and helicase IV, two DNA-dependent adenosine 5'-triphosphatases with helicase activity, have been purified from Escherichia coli and characterized [5].
• We show here that the superfamily I helicase, helicase IV from Escherichia coli, utilizes a conserved glutamine and conserved aromatic residue to interact with ATP [4].

References