Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A mutant of Haemophilus influenzae, designated HM5, carrying a mutation in the rec-1 gene region, is described. This mutant transformed approximately 100-fold less well than does the wild type, but approximately 100-fold better than rec1 mutants. The mutant was less sensitive to UV irradiation and less "reckless" than rec1 mutants. In contrast to rec1 lysogens, HP1c1 lysogens of the mutant were inducible, and during transformation, recombinant-type activity was formed to the same extent as in the wild type. Although the integration of donor DNA was complete, the integrated DNA was not replicated at 36 degrees C. Both the inhibition of replication of the donor-recipient DNA complex and the transformation deficiency could be suppressed when, after DNA entry, the cells were incubated under suboptimal conditions. The loss of colony formation after UV irradiation was suppressible by the same conditions.
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PMID:Characterization of a conditionally transformation-deficient mutant of Haemophilus influenzae that carries a mutation in the rec-1 gene region. 640 7

In the HM5 mutant of Haemophilus influenzae, which carries a mutation in the rec-1 gene region and in which the replication of donor-recipient DNA complexes formed in transformation is inhibited, the transformation frequency could be greatly enhanced by inhibition of protein synthesis during transformation, indicating that transformation in the HM5 mutant induces the synthesis of a protein that inhibits the replication of the donor-recipient DNA complexes. This induction occurred in an early step of the recombination. Synthesis of the wild-type Rec-1 protein after transformation of the HM5 mutant with wild-type DNA could diminish the inhibiting effect on DNA replication. The HM5 mutant synthesized an altered Rec-1 protein (molecular weight, 38,000) whose pI differed from that of the wild type. As a result of the mutation in the rec-1 gene, two other proteins (molecular weights, 37,500 and 43,000) are lacking in the HM5 mutant.
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PMID:Inhibition of DNA replication by transformation in a Haemophilus influenzae mutant carrying an altered Rec-1 protein. 660 58