The Influence of Bacteriocins on Resistance to Infection by Gram-negative Bacteria. I. The Effect of Colicin on Bactericidal Power of Blood*

Abstract

The gram-negative bacteria in the bowel, urine, and tissues in healthy and infected subjects elaborate powerful antibacterial substances known as colicins. Colicins kill gram-negative bacilli of the same, or closely related, species in vitro and have been examined for antibacterial action in vivo. Halbert and Swick (1) found that antibacterial substances, similar to colicins, were elaborated in the tissues of mice with peritoneal and subcutaneous infections produced by Escherichia coli. Branche, Young, Robinet, and Massey (2) obtained evidence that the ability of some E. coli strains to maintain themselves in the human intestine is associated with the production of colicins that suppress competing strains. In order to obtain more definite information on the activity of colicins in vivo, it would be advantageous to administer these substances to animals and examine their effect on the antibacterial properties of the body fluids. Until now, such experiments have been limited by the toxicity that results from an intimate association of colicins with the somatic 0 antigen, or endotoxin. In the present studies, an attempt was made to separate the bactericidal substance from the toxic 0 antigen, so that the colicin could be inoculated into mice and its effect observed on the bactericidal power of their sera. Mice were chosen for this purpose because their sera normally lack bactericidal power (3).

Interaction in the Germfree Mouse Intestine of Colicinogenic and Colicin-Sensitive Microorganisms

“…Our in vivo findings have not been analogous to the in vitro interaction which had signified an obvious dominance by the colicin producer. In vivo studies of colicin production ( 15,16) have left no doubt that colicinogeny is a stable genetic ability. Whether strain CA-62 produces more or less colicin under either of these two conditions is not known.…”

Treatment of plague: promising alternatives to antibiotics

“…Purified bacteriocins could be used for the reduction or elimination of certain pathogens (Braude & Siemienski, 1965;Riley & Wertz, 2002). It has been shown in assays for potency that purified colicins V and K have similar inhibitory activities on a per weight basis to those of the therapeutic antibiotics kanamycin, streptomycin and oxytetracycline (McGeachie, 1970).…”

“…In early studies with partially purified bacteriocins (Montgomerie et al, 1973;Tagg & McGiven, 1972;Turnowsky et al, 1973) or strain pairs differing in their expression (Brubaker et al, 1965;Burrows, 1965;Smith, 1974), the data showed their potential toxicity, and also a relationship between the carriage of bacteriocinogenic factors and the virulence of certain strains. However, studies with purified substances have in many cases failed to confirm toxicity (Braude & Siemienski, 1965;Tagg et al, 1976). Although intraperitoneal injection of 10 mg mutacin B-Ny266 kg 21 did not apparently affect the health of mice, these results will have to be confirmed with more relevant toxicity tests (Mota-Meira et al, 2005).…”

L-Form Infection of the Rat Kidney: Effect of Water Diuresis

“…Several observations suggest that bacterial L-forms may be responsible for persistence of infection in the human urinary tract after seemingly adequate antibiotic therapy, with exacerbation of clinical disease occurring when the organisms revert to the parent bacterial form: (i) Bacteria which commonly cause human urinary tract infection may be readily converted to L-forms (3), (ii) Because of their hyperosmolarity the urine and renal medulla are capable of supporting Lforms (2)(3)(4)(5)(6)(7)(8), and (iii) L-forms have been isolated from the urine in human urinary tract infections and have been associated with recurrence of infection with the same organism after apparent cure ( 3 , 9 ) .…”

“…In previous papers (1)(2)(3) it was shown that several higher plants exhibit antiviral effects on Columbia SK (Col SK) or lymphocytic choriomeningitis (LCM) infection in mice. In this paper we report that another higher plant, Sambzicus sieboldiana (H7443), has been found to have antiviral effects.…”