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PubMed1992

The pyocin Sa receptor of Pseudomonas aeruginosa is associated with ferripyoverdin uptake.

We have used Tn5 mutagenesis to obtain a mutant resistant to pyocin Sa. When grown in iron-deficient succinate medium this mutant lacked an 85-kDa iron-regulated outer membrane protein (IROMP), and expression of a 75-kDa IROMP was increased compared with that in the parent strain. The mutant was deficient in pyoverdin biosynthesis and showed a 95% decrease in transport of ferripyoverdin purified from the parent strain, suggesting that the 85-kDa IROMP is the specific receptor for ferripyoverdin and pyocin Sa. The mutant compensated for the deficiency in pyoverdin biosynthesis and transport by exhibiting a fourfold increase in ferripyochelin transport. The low-level transport of ferripyoverdin in the Sa-resistant mutant, which extended to heterologous pyoverdins from other strains, suggests that Pseudomonas aeruginosa has a second ferripyoverdin uptake system of lower affinity and broader specificity.

Bacterial Outer Membrane Proteins↗
PubMed1993

The inherent DNase of pyocin AP41 causes breakdown of chromosomal DNA.

Pyocin AP41 degrades the chromosomal DNA in sensitive strains of Pseudomonas aeruginosa but has little effect on RNA, protein, and lipid syntheses. In vitro experiments showed that the carboxyl-terminal part of the large subunit of pyocin AP41 carries an inherent DNase that is responsible for its killing action.

Amino Acid Sequence↗
PubMedDate not supplied

[Pyocin typing of 111 strains of Pseudomonas aeruginosa isolated in Tuscany, using the Gillies and Govan method].

Pseudomonas aeruginosa strains from Tuscany have been typed for pyocine production against Govan and Gillies' extended set of indicator strains; results have been expressed following a binary code. Among 111 strains only 6 could not be typed; the remaining 105 strains (94.6%) presented 59 different patterns, 44 of which were represented by one isolate only. The most commonly encountered pattern (n. 8045, corresponding to Govan and Gillies' subtype 1e) was shared by 13 strains. Isolates from outpatients or from the environment tended to a uniform distribution of pyocine patterns; those from two different hospitals tended to group into distinct subtypes.

Bacteriocins↗
PubMedDate not supplied

[Variation in phage typing and pyocin typing of Pseudomonas aeruginosa].

The most frequently used microbiological methods in detecting hospital infection reservoirs caused by bacterial species Pseudomonas aeruginosa (P. a.) are serotyping, phagotyping and pyocin typing. Isolated were 86 strains of P. a. from various material of 38 patients hospitalized in University Clinical Centre in Ljubljana during 1986-7. Efforts have been made to find out the variability of results obtained by phago- and pyocin typing of successively isolated P.a. strains from the same patient. Changes found in these samples have been significant.

Bacterial Typing Techniques↗
PubMed1986

Serological and pyocin typing and antibiotic sensitivity of Pseudomonas aeruginosa strains.

94 strains of Pseudomonas aeruginosa, isolated from hospitalized patients, were typed with serological and pyocinic methods, also testing their sensitivity to 6 antibiotics. The serological method allowed for the typing of almost all the strains (98.9%), (the 0-11 serotype was the most frequent -23.4%-) vs. 80.6% by the pyocinic method. Among those tested, ceftazidime was the most active antibiotic, against the P. aeruginosa strains examined.

Anti-Bacterial Agents↗
PubMed1977

Synergistic activity of gentamicin plus carbenicillin upon Pseudomonas aeruginosa: its relationship with pyocin and antibiotic susceptibility.

The synergistic effect of combinations of gentamicin and carbenicillin, as well as the type or subtype of the pyocins produced, were investigated in 170 strains of Pseudomonas aeruginosa isolated from clinical specimens. A high proportion of strains were synergistically inhibited (73.5%), but among strains producing pyocins 7, 14 and 31, synergy was infrequent or absent. The synergistic effect was more frequent upon gentamicin- or carbenicillin-susceptible strains. However, among untypable strains, synergy was more frequent among gentamicin-resistant strains. Susceptibility to both gentamicin and carbenicillin must be considered if antibiotic susceptibility is to be related to synergy.

Bacteriocins↗
PubMed1976

[Epidemiological studies of P. aeruginosa infections by the typing of pyocine sensitivity (author's transl)].

A standardizing by means of determination of the pyocine sensitivity could be achieved on the basis of 200 strains of P. aeruginosa which had been isolated out of clinical material. It was analyzed semiquantitatively by using a step-scale in five parts. The identical or in a high degree corresponding strains according to the pyocine sensitivity could be registered on the example of the isolated strains of a intensive-care unit by the calculation of the Q-correlation coefficient according to the Q-technique as well as by the determination of the differences in the single reactions using a standardized measure of distance. The epidemiological connexion resulting from that is discussed.

Bacteriocins↗
PubMed1976

[A comparison of antibiotic resistance patterns and pyocine types between strains of Pseudomonas aeruginosa from animal and human sources (author's transl)].

291 strains of Pseudomonas aeruginosa from human bacteriological samples were compared with 102 strains which had been isolated from animals for frequency of pyocine-types and patterns of antibiotic resistance. 146 strains had been isolated from hospitalized patients and 145 from out-patients. More strains of animal origin were sensitive to carbenicillin and tetracyclines compared to strains of human origin. Since the frequency of different pyocine-types is the same in all three groups, it is concluded, that antibiotic resistance may be transferred from man to animal and vice versa via transfer of Pseudomonas aeruginosa.

Animals↗
PubMed1973

An epidemiological study of Pseudomonas aeruginosa in cattle and other animals by pyocine typing.

The high incidence (80.1%) of Pseudomonas aeruginosa pyocine type 1 in bovine mastitis in Israel suggested some degree of selectivity under local conditions. Contrary to other reports, cattle and calves showed a high rate of faecal carriage of this organism. The water supply on farms was often contaminated. The presence of certain pyocine types in the udder, gut or water occasionally led to their transmission from one reservoir to another; however, many types did not seem to spread.P. aeruginosa was found in association with infections in various animals and was present in many locations such as a mouse breeding house and a chick hatchery.

Abattoirs↗
PubMed1969

Pyocine typing of clinical strains of Pseudomonas aeruginosa.

A total of 954 clinical isolates of Pseudomonas aeruginosa were typed by their ability to produce pyocines. The strains of Pseudomonas were isolated from urines, bloods, sputa, stools, and miscellaneous infectious exudates or tissue of patients of the Mayo Clinic and four associated hospitals. About 80% of the typable strains could be grouped into three major pyocine types: A (30.9%), B (34.8%), and D (14.1%). These large groups could be divided into subtypes by using additional indicator strains. There was no significant difference in the distribution of types by either institutional or specimen source, except that urine specimens yielded the highest percentage of one type. By this procedure, 93% of all isolates could be typed. Repeated typing of serially transferred strains indicated that the procedure has a high degree of reliability. Several strains exhibited extreme fluctuation in inhibition pattern. The procedure is a simple and reliable method to monitor the patterns of nosocomial infections due to P. aeruginosa.

Bacteriocins↗
PubMed1972

Epidemiology of pseudomonas aeruginosa in a burn hospital: evaluation of serological, bacteriophage, and pyocin typing methods.

In a retrospective study 36 cultures of Pseudomonas aeruginosa, isolated from patients with fatal Pseudomonas burn wound sepsis and from burned patients with nonfatal P. aeruginosa infections, were used to evaluate the consistency and reliability of serological, phage, and pyocin typing as epidemiological tools. Frequency distributions of positive reactions were analyzed by a computer in a 3-way chi-square test, and a high degree of consistency was demonstrated for each method. From these data, 75% of the cultures were differentiated by serological, 90% by phage, and 100% by pyocin typing. There was no significant difference among organisms isolated from fatal cases of burn wound sepsis and organisms from patients with nonfatal infections (chi(2) = 0.3418; P = 0.9870). The combined typing system was a sensitive and reliable epidemiological tool for intraspecific differentiation of P. aeruginosa.

Bacteriocins↗
PubMed1973

Simplified method for producing pyocins from Pseudomonas aeruginosa.

Good yields of pyocin are obtained when Pseudomonas aeruginosa is grown in Trypticase soy broth (without glucose) (BBL) plus 1% potassium nitrate. As a result, pyocin production for routine epidemiological typing can be done in screw-cap tubes, without mechanical agitation or mitomycin C induction.

Bacteriocins↗
PubMed1967

Electron microscopy of the combination of antibodies with flagellar antigen and with a pyocine.

Micrographs are presented of antibodies in combination with flagella of Salmonella typhi and with a phage-bound pyocine Rmc, which is supposed to be the tail of a defective bacteriophage from Pseudomonas aeruginosa. The pyocine preparation seems to offer advantages for the study of antibody-antigen complexes. Under the conditions of our experiments, the surfaces of the antigenic structures are saturated with antibody layers approximately 95 A in thickness, i.e., slightly less than half the accepted lengths of 7S antibody molecules. Our interpretation is that the antibody is attached by combining sites at the ends of the molecules to form loops along the surface of the antigenic structures.

Animals↗
PubMed1979

Epidemiological markers for Pseudomonas aeruginosa. VII. Nosocomial occurrence in urological ward. Comparison of two phage typing sets, pyocine typing, and serogrouping.

A comparison of two pyocine typing methods with serogrouping, and two phage typing sets has been made. In one instance, a contaminated bladder irrigation fluid of 0.05% silver nitrate solution caused a series of urinary tract infections. By all systems, fewer of the presentstrains were typable than usual. Among the phage typing sets the one developed by LINDBERG et al. typed only 66% whereas that selected by BERGAN typed 83%, both less than observed previously. The set of LINDBERG et al. also rendered longer pattern codes, and yielded more variable results with related strains. A set of pyocine indicator strains, selected among the strains to be typed, was more suitable than one developed elsewhere. Comparison of five different methods of epidemiological typing of Ps. aeruginosa indicated that phage typing alone is not entirely satisfactory for this species and should therefore always be combined with serogrouping.

Bacteriophage Typing↗
PubMed1987

Prevalence of pyocin types of P. aeruginosa in a university hospital during 1981-1986.

Strains of Pseudomonas aeruginosa isolated from patients in the University of Granada (Spain) from 1981 to 1986 were pyocin-typed in order to determine which types were the most common. The proportions of typable and non typable strains were similar to those obtained by other authors. A high percentage of typable strains were unclassifiable (UC) according to Govan's method. The most frequent types of typable strains were 580 (55 of Govan), 270 (UC), 280 (UC), 570 (UC), 670 (73 of Govan), 113 (10 of Govan), 470 (86 of Govan) and 180 (58 of Govan). These types were responsible for the appearance of several nosocomial outbreaks during the years of this study. Types 580, 113 and 280 remained constant for these six years; for this reason, they can be considered endemic of our hospital.

Bacteriophage Typing↗
PubMed1993

A novel transposon-like structure carries the genes for pyocin AP41, a Pseudomonas aeruginosa bacteriocin with a DNase domain homology to E2 group colicins.

The genetic determinant for pyocin AP41, a bacteriocin produced by Pseudomonas aeruginosa, has been cloned. The determinant is located on the chromosome flanked by a pair of inverted repeats, forming a transposon-like structure (TnAP41). TnAP41 possesses some features characteristic of the Tn3 family of transposons. Based on a comparison with the structure of the corresponding region of the chromosome of a non-producer strain, we propose that P. aeruginosa has acquired pyocinogeny by the transposition of TnAP41 into the chromosome. The determinant comprises two ORFs encoding the protein subunits responsible for the killing action (the large component) and immunity (the small component). Amino acid sequences of the C-terminus of the large component (the deoxyribonuclease domain) and the immunity protein show remarkable homology to those of E2 group colicins, suggesting that these bacteriocins, which are produced by distantly related species, have originated from a common ancestor.

Amino Acid Sequence↗
PubMed1989

Structure and heterogeneity of the oligosaccharides from the lipopolysaccharides of a pyocin-resistant Neisseria gonorrhoeae.

The compositions and partial structures of the oligosaccharides from the lipopolysaccharides (LPS) of a pyocin-resistant Neisseria gonorrhoeae (strain JW31R) have been determined by liquid secondary ion mass spectrometry (LSIMS), tandem mass spectrometry, and methylation analysis. Four major structures were identified with Mr 2123, 2000, 1961, and 1838, as well as seven species of lower abundance of Mr 1758-1272. The largest of the major oligosaccharides (Mr, 2122) consists of 3-deoxymanno-2-ketooctulosonic acid (KDO)-Hep2GalNAcGlcNAcGal4Glc2 (Hep, heptose) and phosphoethanolamine (PEA). The smaller oligosaccharides are truncated versions of this larger oligosaccharide. The oligosaccharides consist of a common triantennary structure containing KDO at the reducing terminus attached to a heptose disaccharide. A hexose (Hex)2-3 branch is attached to the heptose linked directly to KDO and a GalNAc-Hex3, GlcNAc, and PEA are separately attached to the second heptose. These oligosaccharides are the first structures to be determined for a gonococcal LPS and should further our understanding of the structural and antigenic diversity of these glycolipids.

Bacteriocins↗