PubMed Health⌕ Search

Biomedical subjects

C C Brinton

Publications and source records attributed to C C Brinton.

33 records · Page 2Linked to original sources
PubMed1978

Immunization of suckling pigs against enterotoxigenic Escherichia coli-induced diarrheal disease by vaccinating dams with purified 987 or K99 pili: protection correlates with pilus homology of vaccine and challenge.

Pregnant gilts were vaccinated with purified strain 987 pili (987P), strain K99 pili, or a saline-formaldehyde control. Suckling pigs born to vaccinated gilts were allowed to consume colostrum and were then challenged intragastrically with one of three enterotoxigenic Escherichia coli strains: 987 (O9:K103, 987P:NM), 74-5208 (02O:K101, 987P:NM) or 431 (O101:K30, 99:NM). In litters where the dam was vaccinated with the same pilus as that possessed by the challenge organism, the incidence and duration of diarrhea and the degree of intestinal colonization (either duration or extent) were less than those of the other vaccine groups. Surviving pigs in the homologous vaccine groups also had better weight gains than pigs in the other vaccine groups. The experiments extend and confirm previous reports that vaccination of the dam with purified pili confers protection to neonatal suckling pigs against diarrheal disease caused by enterotoxigenic E. coli strains that possess the same pili. Protection did not extend to enterotoxigenic strains possessing different pili.

Animals↗
PubMed1977

Isolation and characterization of Escherichia coli phase variants and mutants deficient in type 1 pilus production.

Type 1 pili of Escherichia coli are the prototype of the somatic class of pili found on many strains of bacteria. As a first step in the genetic analysis of type 1 piliation, an extensive series of nonpiliated derivatives of E. coli K-12 strain AW405, was characterized to produce attached or free pili when examined in the antiserum or appeared to produce attached or free pili when examined in the electron microscope. The derivatives fell into two classes; phase variants and mutants. Phase variants that formed colonies of two distinctive types, one associated with a predominantly piliated (P+), and the other associated with a nonpiliated (P-) phase, were obtained. Each phase could give rise to the other at a relatively high rate, which was greater in the P- to P+ direction during culture in unshaken liquid medium. In addition, 77 Pil- mutants were selected on the basis of a subtle difference in colonial morphology. The mutants reverted, if at all, at a much lower rate than that of the P- to P+ change. The stability of Pil- derivatives grown in unshaken liquid medium was used as a criterion for distinguishing between phase variants and mutants, Phase variation also effected colonial morphology and chemotactic swarming. These properties did not directly depend upon piliation since Pil- mutants were only slightly altered in colonial form and unaltered in chemotactic swarming. Piliation of Pil+ bacteria was quantitatively affected by growth conditions.

Chemotaxis↗
PubMed1977

Genetic complementation analysis of Escherichia coli type 1 somatic pilus mutants.

A genetic complementation analysis of 75 stable nonpiliated mutants of a type 1 piliated strain of Escherichia coli K-12, AW405, was performed. Strains containing pairs of pil mutations were constructed by the infectious transfer of an F101 plasmid containing one pil mutation into E. coli K-12 AW 405 containing another pil mutation. The presence or absence of type 1 pili on the merodiploid strains was determined by agglutination with type 1 pilus antiserum. All 75 mutants fell into one of four complementation groups. The pattern of complementation defined three cistrons involved in pilus formation, pilA, pilB, and pilC. The fourth complementation group was composed of a large number of mutants defective in both pilA and pilB functions.

Escherichia coli↗
PubMed1969

Mechanical removal of F pili, type I pili, and flagella from Hfr and RTF donor cells and the kinetics of their reappearance.

The effect of mechanical agitation (blending) on the removal of F pili, type I pili, and flagella from Hfr (high-frequency recombinant) and resistance transfer factor (RTF) fi(+)Escherichia coli cells was studied by electron microscopy. The reduction in number and length of appendages was measured as a function of blendor speed under standard conditions of temperature, medium, cell density, and blendor configuration. F pili and flagella were removed within the same narrow range of blendor speeds. Type I pili were removed within a higher and broader range of speeds. The speed which reduced the average length of type I pili to 50% was 3.5 times the speed which reduced the average length of F pili to 50%. None of the speeds employed inhibited cell growth, viability, or the ability to produce cell appendages. The kinetics of reappearance of F pili and type I pili after removal by blending were also different. F pili grew out very rapidly, reaching 50% of their full length in 30 sec and their full length in 4 to 5 min. The number of attached F pili per cell also increased rapidly, reaching a constant value in 4 to 5 min. After 5 min, F pilus lengths were distributed around a modal value of about 1.2 mum, and the numbers of F pili per cell were distributed according to a Poisson distribution, with an average of 1.0 per cell. These reappearance kinetics, length distributions, and number distributions are consistent with a model of F-pilus outgrowth in which new F pili appear at random locations on the cell surface at an average rate of about once every 4 min, grow to their characteristic length in about 4 min, and then separate from the cell. F pili which had separated could absorb to the cells, leading to the presence of two classes of F pili on cells: those in the process of natural out-growth and those attached by absorption. Type I pili increased in length much more slowly than did F pili, although the fraction of cells having visible type I pili increased very rapidly after blending because of the large number of type I pili per cell. The fraction of flagellated cells increased even more slowly, reaching only 30% of the unblended fraction in 30 min. The application of blending spectra and reappearance kinetics to the identification of cell functions with surface structures is discussed.

Coliphages↗
PubMed1969

Functions of F pili in mating-pair formation and male bacteriophage infection studies by blending spectra and reappearance kinetics.

The extent of removal at various blending speeds (blending spectrum) and the kinetics of reappearance after blending of the ability of male Escherichia coli bacteria to form mating pairs, to adsorb and be infected by ribonucleic acid male phage, and to adsorb and be infected by deoxyribonucleic male phage were identical to the blending spectrum and reappearance kinetics of microscopically visible F pili. The same results were obtained with an Hfr (high-frequency recombinant), F', or resistance transfer factor (RTF) fi(+) mating system. Blending did not affect the viability, growth rate, ability to adsorb T4 phage, or ability to produce new F pili at any of the speeds used. It can be concluded that microscopically visible F pili are an absolute requirement for all three functions. Three classes of F pili have been found in bacterial cultures: attached, adsorbed, and free. Bacteria with adsorbed F pili in addition to attached ones were proportionately more susceptible to male phage infection, suggesting that adsorbed F pili may be at least partially functional. Free F pili did not compete with bacteria for phage. Some implications of the virus-like nature of F-pilus outgrowth for the mechanisms of mating and male phage infection are discussed.

Adsorption↗
PubMed1968

Inhibition of bacterial conjugation by ribonucleic acid and deoxyribonucleic acid male-specific bacteriophages.

Both deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) male-specific phages, with an F-specific host range, inhibited the bacterial mating process of Escherichia coli. DNA phages prevented the formation of mating pairs but had no effect on mating pairs once they were formed. A step in RNA phage infection, prior to RNA penetration, prevented the formation of mating pairs and, in addition, prevented a fraction of existing mating pairs from completing the mating process. These findings are compatible with the hypothesis that donor cells have a single surface structure involved in both conjugation and male-phage adsorption and that this element is the F pilus.

Binding Sites↗
PubMed1962

UTILIZATION OF CARBOHYDRATES AND METABOLIC INTERMEDIATES BY PILIATED AND NONPILIATED BACTERIA.

Wohlhieter, J. A. (Walter Reed Army Institute of Research, Washington, D.C.), C. C. Brinton, Jr., and L. S. Baron. Utilization of carbohydrates and metabolic intermediates by piliated and nonpiliated bacteria. J. Bacteriol. 84:416-421. 1962.-The rate of aerobic and anaerobic metabolism of piliated and nonpiliated bacteria was studied in an effort to determine whether the presence of these surface structures altered the metabolic activity of bacteria. Respiration was measured manometrically when various piliated and nonpiliated strains metabolized glucose and several Krebs-cycle intermediates. Spontaneously produced nonpiliated variants of piliated cells were examined, but no difference in the rate of either aerobic or anaerobic metabolism was observed. Piliated and nonpiliated recombinants of a mating of Escherichia coli and Salmonella typhosa had different metabolic rates than the parent strains, but it was shown that these differences were not related to piliation. Clones of piliated and nonpiliated cells isolated from other crosses showed no difference between their respiration rate and that of either parent. Piliated and nonpiliated strains could mutate to higher rates of substrate utilization with no concomitant change in piliation. Since respiration and piliation can mutate independently and segregate independently in genetic crosses, we therefore conclude that there is no direct physiological relationship between them.

Journal Article↗
PubMedDate not supplied

Intestinal colonization and antibody response.

Rapid bacterial colonization of the gastrointestinal tract takes place immediately after birth. Only a few of the Escherichia coli strains colonizing the gut of healthy full-term neonates expressed MS pili. On the other hand, most E. coli strains isolated carried MR pili resembling the P-fimbriae which are a known virulence factor for pyelonephritogenic E. coli. The presence of serum antibodies against pili and K antigens of E. coli after vaccination did not influence the capacity of E. coli to colonize and persist in the intestine of experimental animals.

Animals↗