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The fixA and fixB Genes Are Necessary for Anaerobic Carnitine Reduction in Escherichia coli. Angelique Walt, 2002.In Escherichia coli, the use of carnitine as a terminal electron acceptor depends on a functional caiTABCDE operon . It had been suggested that the adjacent but divergent fixABCX operon is also required for carnitine metabolism, perhaps to provide electrons for carnitine reduction . We have constructed E . coli fixA and fixB mutants and find that they are unable to reduce carnitine to  -butyrobetaine under anaerobic conditions .
Bacteriophage HP2 of Haemophilus influenzae. Bryan J. Williams, 2002.Temperate bacteriophages effect chromosomal evolution of their bacterial hosts, mediating rearrangements and the acquisition of novel genes from other taxa . Although the Haemophilus influenzae genome shows evidence of past phage-mediated lateral transfer, the phages presumed responsible have not been identified . To date, six different H . influenzae phages are known; of these, only the HP1/S2 group, which lyosogenizes exclusively Rd strains (which were originally encapsulated serotype d), is well characterized . Phages in this group are genetically very similar, with a highly conserved set of genes . Because the majority of H . influenzae strains are nonencapsulated (nontypeable), it is important to characterize phages infecting this larger, genetically more diverse group of respiratory pathogens . We have identified and sequenced HP2, a bacteriophage of nontypeable H . influenzae . Although related to the fully sequenced HP1 (and even more so to the partially sequenced S2) and similar in genetic organization, HP2 has a few novel genes and differs in host range; HP2 will not infect or lysogenize Rd strains . Genomic comparisons between HP1/S2 and HP2 suggest recent divergence, with new genes completely replacing old ones at certain loci . Sequence comparisons suggest that H . influenzae phages evolve by recombinational exchange of genes with each other, with cryptic prophages, and with the host chromosome .
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