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J Mikucki

Publications and source records attributed to J Mikucki.

At least 37 records · Page 2Linked to original sources
PubMed1996

[Coagulase-negative staphylococci isolated from cases of infective endocarditis].

In this study we investigated the properties of 47 strains of coagulase-negative staphylococci (CNS) isolated from patients with infective endocarditis (IE) and 61 strains of CNS isolated from the skin flora of healthy people. Significant differences between the properties of CNS from IE and from the skin flora were seen in the production of protease, lipase, fibrinolysin, siderophore and the ability of hydrophobic CNS strains to adhere to buccal epithelial cells. CNS from IE and from the skin flora did not differ in the production of glycocalyx, capsule, hemolysin and fibronectin and collagen binding. Multiple resistant strains were present among CNS isolated from patients with IE.

Cheek↗
PubMed1996

[Staphylococcal utilization of siderophores produced by bacilli of the genus Bacillus].

The ability of utilization by 24 staphylococcal strains of the siderophores of B. megaterium PCM 2010 and B. subtilis S was investigated. B. megaterium PCM 2010 produced hydroxamate class siderophores and B. subtilis S-catecholate class. The majority of staphylococcal strains--thirteen--could utilize these siderophores: eight strains from both these species and three strains did not possess any receptors for these chelators. The staphylococcal strains producing catecholate siderophores utilized catecholate chelators from B. subtilis S.

Bacillus↗
PubMed1995

The interchangeability of siderophores in Staphylococci.

The functional interchangeability of siderophores among 90 strains belonging to 26 species of genus Staphylococcus was tested. Among the species which synthesized siderophores most commonly utilized (the best donors) were S. epidermidis, S. aureus, S. cohnii, S. hominis and S. simulans. The species which utilized the widest range of exogenous siderophores from other species (the best recipient) were S. epidermidis, S. saprophyticus, S. kloosii and S. schleiferi. The donor and recipient of the widest range of siderophores was S. epidermidis. The potential ability to exchange siderophores as well as the range of their functional interchangeability in staphylococci were found as the features characterizing individual strains.

Chelating Agents↗
PubMed1994

The occurrence of siderophores in staphylococci.

In 180 staphylococcal strains of diverse origin belonging to 26 species a hydroxamate class siderophore was detected with chemical test. In 65% of investigated strains it was identified by biological assay as aerobactin. A correlation between hydroxamate siderophore production, species affiliation and pathogenicity was not found. In 14 (7.8%) strains a catechol class siderophore, beside aerobactin, was detected.

Catechols↗
PubMed1992

Staphylococcal L-asparaginase: catabolic repression of synthesis.

The regulation mechanism of production of staphylococcal L-asparaginase was investigated. The role of cAMP in regulation of its synthesis was confirmed. Production of L-asparaginase from S. aureus NCTC 4135 was inhibited by all carbon sources, mono- and disaccharides added to the growth medium. The strongest inhibition was caused by saccharose and maltose, whereas weaker by galactose, lactose, mannitol and mannose. It was found that exogenous cAMP in the presence of carbon sources stimulated synthesis of the investigated enzyme.

Asparaginase↗
PubMed1992

[The role of bacterial metabolism in transformation of non-mutagenic compounds into mutagens. I. Participation of Escherichia coli nitroreductase in creation of mutagens from non-mutagenic new pesticides].

Investigations concerned Escherichia coli nitroreductase in creation of mutagens from non-mutagenic pesticides-derivatives of urea. Three new compounds were studied: N-phenyl-N'-methylurea (IPO 4328), N-methyl,N-(2-hydroxyethyl)-N'phenylurea (IPO 2363), N-(2-hydroxyethyl), N-methyl-N'-(3,4 dichloroethyl) urea, and diurone-3-(3,4 dichlorophenyl)-1,1 dimethylurea. These compounds were incubated in anaerobic conditions with cells of E. coli K-12 (KF) strain and nitrate or nitrite. Using Ames test, mutagenicity of resulting metabolites was investigated. It was found that during incubation of herbicide IPO 4328 with cells of E. coli K-12 (KF) and nitrate, mutagenic product for strain of S. typhimurium TA 1537 is created. Very weak mutagenic metabolite for the same strain was appearing during incubation of herbicide IPO 2363 with cells of E. coli K-12 (KF) in presence of nitrite. Incubation of investigated compounds with E. coli K-12 (KF) cells alone did not result in appearance of mutagenic substances. Thus, role of Escherichia coli in creation of mutagenic compounds from non-mutagenic derivatives of urea consisted of nitrite from nitrate production with participation of nitroreductase, which afterwards in absence of bacteria or action of their enzymes reacted with investigated pesticides.

Escherichia coli↗
PubMed1992

[Role of bacterial metabolism in transformation of non-mutagenic compounds into mutagens. II. Participation of bacteria producing urease in degradation of pesticides--urea derivatives].

Participation of bacteria producing urease: Proteus mirabilis and Staphylococcus epidermidis in degradation of pesticides--urea derivatives, was investigated. Four new compounds were studies: N-/(3-trifluoromethyl)phenyl/N'-(2-cyanoethyl)-urea (IPO 6584), N-(4-chlorophenyl)-N'-(2-hydroxyethyl)-N'-ethylurea (PO 6236), N-(4-chlorophenyl)-N'-(2-hydroxyethyl), N'-propyl-urea (IPO 6237), N-(2-hydroxyethyl), N-methyl-N'-(3,4 dichlorophenyl)-urea (IPO 3102), pesticide reference standard--thiram fungicide--tetramethyl-bis-thiocarbamyl disulfide, and rodenticide-alpha-naphthylthiourea (ANTU). Investigated compounds were incubated with cells of P. mirabilis 4508 ans S. epidermidis CCM 2448 and commercial preparation of urease from beans. Mutagenicity of resulting metabolites was then studies by the Ames test. All compounds were decomposed by bacteria used in this study, as well with beans urease with different activity. Reaction products did not exhibit mutagenic activity for test strains S. typhimurium his- TA97a, TA98, TA100 and TA102.

Biotransformation↗
PubMed1991

Staphylococcal L-asparaginase: enzyme kinetics.

The ph optimum of purified staphylococcal L-asparaginase (EC 3.5.1.1) was found to be between 8.6 and 8.8. The temperature optimum was 30 degrees-32 degrees C and the highest reaction rate occurred at 30 degrees C. The KM of the enzyme calculated from Lineweaver-Burk plot was 3.71 x 10(-2) M. Besides L-asparaginase, the substrate specificity of enzyme was restricted to N-alpha-acetyl-L-asparagine. D-asparagine, L-aspartic acid and D-glutamic acid were competitive inhibitors. Hg2+ and Cu2+ cations strongly inhibited the enzyme while Na+ and K+ cations strongly stimulated activity. Two SH-groups could be detected after enzyme denaturation with guanidine.

Asparaginase↗
PubMed1989

Poly-beta-hydroxybutyric acid in staphylococci.

Poly-beta-hydroxybutyric acid (PHB) was extracted from various species of staphylococci isolated from different sources. IR and UV spectrophotometry and NMR analysis revealed that the compound consisted only of the beta-hydroxybutyrate. The PHB level in the richest strain among investigated staphylococci is about 64-fold less than in bacilli. The intrinsic viscosity number of this polymer is more than twice greater in the case of the staphylococcal product than that of bacilli.

Hydroxybutyrates↗
PubMed1986

[Effect of Neowetadina and Polyvaccinum on serum levels of immunoglobulins and total proteins in calves during the industrial fattening process].

The usefulness of nonspecific stimulating preparations-Neowetadina (Biowet) and Poliwakcyna (Polfa) for stimulation of the serum level of immunoglobulins of the classes IgG, IgA and IgM and total protein was determined in calves of the black and white breed at the age of 9-10 weeks (average body weight 75-80 kg) over 8 weeks from the onset of industrial fattening in technological groups. The stimulants were given in single intramuscular injections at the following doses: 0.08 and 0.4 ml of Neowetadina per 1 kg of body weight, 0.4 ml of Poliwakcyna forte per 1 kg of body weight. The level of the particular classes of immunoglobulins in the calf sera was determined by radial immunodiffusion according to Mancini et al., modified by Fahey and McKelvey, and that of total protein by the biuret method. The serum of the IgG class immunoglobulins increased statistically significantly (P less than or equal to 0.05), starting from the 4th week after the administration of the preparations and reached its maximal value in the 5th week. However, the serum level of IgA increased in the 8th week of observation. Poliwakcyna and Neowetadina effected only slightly the increase of the serum level of IgM immunoglobulins. The preparations also stimulated the increase of total protein level in the blood serum of the calves.

Adjuvants, Immunologic↗
PubMed1984

Concentrations of cloxacillin and erythromycin in the tonsils of children after administration of therapeutic doses.

The treatment of infections in the ring of Waldeyer in children is an ever present problem. Most infections are caused by group A streptococci, and various antibiotics are routinely used for their treatment. In many cases, however, this treatment is ineffective as demonstrated by prolonged disease duration and recurrences. This may be due to the resistance of the pathogens to the used antibiotic, too low dose, or inadequate penetration of the drug into the focus of infection. To explain this problem the reported investigation was undertaken carrying out bacteriological investigations of the removed tonsils and determining antibiotic concentrations in tonsil homogenates and in the serum after cloxacillin and erythromycin treatment of 45 children aged 4-14 years subjected to tonsillectomy or adenotomy . It was found that the most frequent aetiological factors in angina and adenoiditis were group A streptococci. Cloxacillin and erythromycin are the antibiotics penetrating well into the lymphoid tissue and reaching high concentrations in the focus of infection but the courses of treatment should not be shorter than 10 days.

Adolescent↗
PubMed1983

Rapid methods in studies on the genetic changes induced by chemicals.

Eight new compounds of the quaternary ammonium salts group were investigated for mutagenicity. Tests were carried out on onion roots (Allium test) and on bacteria (Ames' test) to examine the mitosis disturbances. None of the compounds produced mutagenic activity in the bacterial test, whereas in the Allium test two compounds produced a strong effect on mitotic cell division.

Animals↗