Role of Unsaturated Fatty Acid Biosynthesis in Virulence of Streptococcus mutans

Department of Microbiology and Immunology, Center for Oral Biology, Rochester, NY 14642, USA.
Infection and Immunity (Impact Factor: 3.73). 04/2007; 75(3):1537-9. DOI: 10.1128/IAI.01938-06
Source: PubMed


An insertionally inactivated fabM strain of Streptococcus mutans does not produce unsaturated membrane fatty acids and is acid sensitive (E. M. Fozo and R. G. Quivey, Jr., J. Bacteriol. 186:4152-4158, 2004). In this study, the strain was shown to be poorly transmissible from host to host. Animals directly infected with the fabM strain exhibited fewer and less severe carious lesions than those observed in the wild-type strain. Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Download full-text


Available from: Elizabeth M Fozo, Aug 28, 2014
21 Reads
  • Source
    • "Inactivation of the gene responsible for biosynthesis of monounsaturated fatty acids, fabM, resulted in a strain that was extremely sensitive to low pH and unable to maintain ΔpH (Fozo & Quivey, 2004a). Rats infected with the fabM mutant exhibited substantially reduced caries, as compared to the parent strain (Fozo et al., 2007). "
    [Show abstract] [Hide abstract]
    ABSTRACT: The complete genome sequence of Streptococcus mutans, a bacterial pathogen commonly associated with human dental caries, was published in 2002. The streamlined genome (2.03 Mb) revealed an organism that is well adapted to its obligately host-associated existence in multispecies biofilms on tooth surfaces: a dynamic environment that undergoes rapid and substantial fluctuations. However, S. mutans lacks many of the sensing systems and alternative sigma factors that bacteria often use to coordinate gene expression in response to stress and changes in their environment. Over the past 7 years, functional genomics and proteomics have enhanced our understanding of how S. mutans has integrated the stress regulon and global transcriptional regulators to coordinate responses to environmental fluctuations with modulation of virulence in a way that ensures persistence in the oral cavity and capitalizes on conditions that are favourable for the development of dental caries. Here, we highlight advances in dissection of the stress regulon of S. mutans and its intimate interrelationship with pathogenesis.
    Microbiology 12/2008; 154(Pt 11):3247-55. DOI:10.1099/mic.0.2008/023770-0 · 2.56 Impact Factor
  • Source
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: While the muscles that move the eyes, the extraocular muscles (EOM), are well endowed with proprioceptors, afferent signals from these receptors are usually assumed to play little or no role in the control of eye movement. In a series of experiments, a suction contact lens was used to impose movements on one eye, thus inducing afferent signals. Single unit activity was recorded centrally (to examine the interactions between EOM afferent signals and visual or vestibular signals), or the movements of the other eye were measured (to investigate their effects on the output of the oculomotor system). In a model preparation, the decerebrate pigeon, EOM afferent signals modified single unit activity in the medial vestibular nucleus, and the third and sixth motor nuclei, during sinusoidal vestibular stimulation. When one eye was moved to mimic the vestibulo-ocular reflex (VOR), movement faster than required for compensation for a given head velocity reduced the gain of single unit vestibular responses. In awake, alert pigeons the overall output of the VOR, as evidenced by movements of the other eye, was modified. In humans, when one eye was impeded, the saccades and smooth pursuit executed by the other eye were altered. Taken together, these results suggest that EOM afferent signals play a functional role in the shaping of eye movement.
    Progress in brain research 02/2008; 171:29-35. DOI:10.1016/S0079-6123(08)00605-5 · 2.83 Impact Factor
Show more