Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “BACTERIA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources
PubMed1995

An enhanced broad-host-range vector for gram-negative bacteria: avoiding tetracycline phototoxicity during the growth of photosynthetic bacteria.

A mobilizable, broad-host-range (bhr) plasmid was derived from the widely used IncP1 vector pRK415. The new vector, pRKD418, contains an additional resistance gene and an enlarged multiple cloning site (MCS) region. The optimal growth of pRK415-containing bacteria under photosynthetic conditions generally requires the use of optical filters to protect the selective antibiotic tetracycline (Tc) from photooxidation with the resulting production of toxic photoproducts; pRK415 is not stably maintained in the absence of selective pressure. The addition of a trimethoprim-resistant dihydrofolate reductase-encoding gene provided for optimal photosynthetic growth in the presence of a selective antibiotic without any special apparatus. The presence of an antibiotic marker not found in commonly used cloning vectors in many cases facilitates the subcloning of inserts into the bhr plasmid. The new MCS region provides further cloning flexibility with at least sixteen available restriction sites. Easily constructed derivative plasmids, exemplified by pRKD418KmE, provide a convenient screening procedure for the detection of recombinants during subcloning.

Base Sequence↗
PubMed2000

The gene encoding mycobacterial DNA-binding protein I (MDPI) transformed rapidly growing bacteria to slowly growing bacteria.

Pathogenic species of Mycobacterium are slowly growing intracellular bacteria. Slow growth is important for the parasitism of these organisms and chronicity of the disease, but its precise mechanism has not been elucidated. Recently, we found that a novel DNA-binding protein (MDPI) was expressed (7-10% in total protein) in mycobacteria, such as Mycobacterium bovis bacillus Calmette-Guérin, Mycobacterium tuberculosis, and Mycobacterium leprae. In this study, we observed that MDPI interfered with replication, transcription, and translation in the analysis in in vitro E. coli cell-free macromolecular biosynthesizing systems. Furthermore, MDPI inhibited the rapid growth of both Escherichia coli and Mycobacterium smegmatis, and NH(2)-terminal second amino acid, asparagine, was observed to be important in terms of this function. These data suggest an important role of MDPI for suppression of growth rates of mycobacteria.

Bacterial Proteins↗
PubMed1986

Antagonism of Lactic Acid Bacteria against Phytopathogenic Bacteria.

A variety of lactic acid bacteria, isolated from plant surfaces and plant-associated products, were found to be antagonistic to test strains of the phytopathogens Xanthomonas campestris, Erwinia carotovora, and Pseudomonas syringae. Effective "in vitro" inhibition was found both on agar plates and in broth cultures. In pot trials, treatment of bean plants with a Lactobacillus plantarum strain before inoculation with P. syringae caused a significant reduction of the disease incidence.

Journal Article↗
PubMed1994

Evidence for natural horizontal transfer of tetQ between bacteria that normally colonize humans and bacteria that normally colonize livestock.

Though numerous studies have shown that gene transfer occurs between distantly related bacterial genera under laboratory conditions, the frequency and breadth of horizontal transfer events in nature remain unknown. Previous evidence for natural intergeneric transfers came from studies of genes in human pathogens, bacteria that colonize the same host. We present evidence that natural transfer of a tetracycline resistance gene, tetQ, has occurred between bacterial genera that normally colonize different hosts. A DNA sequence comparative approach was taken to examine the extent of horizontal tetQ dissemination between species of Bacteroides, the predominant genus of the human colonic microflora, and between species of Bacteroides and of the distantly related genus Prevotella, a predominant genus of the microflora of the rumens and intestinal tracts of farm animals. Virtually identical tetQ sequences were found in a number of isolate pairs differing in taxonomy and geographic origin, indicating that extensive natural gene transmission has occurred. Among the exchange events indicated by the evidence was the very recent transfer of an allele of tetQ usually found in Prevotella spp. to a Bacteroides fragilis strain.

Animals↗
PubMed2006

Capsular antigens of bacteria. Capsular antigens as the basis of vaccines against pathogenic bacteria.

The role of bacterial capsular antigens represented in capsular polysaccharides and exoglycans in pathogenicity and virulence of bacteria is discussed in this review. Using capsular antigens for vaccines against severe diseases caused by capsular microorganisms is considered in detail. The use of conjugates of capsular polysaccharides and their fragments with proteins and peptides for vaccine as well as using liposomes as adjuvants for the capsular antigens are described. Data concerning structural elucidation of bacterial capsular antigens are given in the first part of this review.

Adjuvants, Immunologic↗
PubMed1990

[Studies on resistant mechanisms in the resistant bacteria to chlorhexidine. II. Chemical components of the cell membrane and the electron microscopical observation of cell surface structure of chlorhexidine-resistant bacteria].

The mechanisms of resistance of Serratia marcescens and Pseudomonas cepacia to chlorhexidine were studied. Leakage of the cellular component such as protein was observed in a chlorhexidine sensitive strain (S1) of S. marcescens when S1 was treated with chlorhexidine at 40 micrograms/ml concentration, while this phenomenon was not observed in a resistant strain (R1). The following observations were made concerning about cell surface structure in the chlorhexidine sensitive and resistant strains of S. marcescens by chemical analyses of membrane components and electron microscopical studies of the thin sections of the cells. (1) When the S1 strains was treated with chlorhexidine, the outer membrane of the cells formed a wrinkled surface with irregular blebs, and some of which broke out to form various sizes of granules. The R1 strain did not undergo such morphological changes under the same conditions used in the sensitive strain. (2) A prominent protein with apparent molecular weight of 45 K was found exclusively in the R1 strain of S. marcescens as major outer membrane protein, while it was not found in S1 strain. (3) There were no differences in the composition of phospholipids and the amount of 3-hydroxytetradecanoic acid between S1 and R1 strains of S. marcescens. In Pseudomonas cepacia PCJ1 which is resistant to chlorhexidine, 50 K protein was also observed as a major protein of outer membrane of the cells. In contrast to the strain, a mutant of the strain, #102 which was obtained from PCJ1 strain by the treatment with methanesulfonic acid ethylester, did not possess the 50 K protein in its outer membrane. These data suggested that outer membrane components of bacteria were related importantly in resistant mechanism.

Bacterial Proteins↗
PubMed1988

[Differences in nitrogen and RNA contents between free bacteria and bacteria fixed to food particles in the rumen contents, in the case of different diets; consequences for estimating the ratio of bacterial nitrogen in duodenal nitrogen].

Differences in nitrogen and RNA contents were found between liquid-associated and solid-adherent bacteria isolated from the reticulo-rumen of ruminants offered various diets. Consequences on the estimation of the bacterial nitrogen flow to the duodenum are discussed.

Animal Feed↗
PubMed1984

[Intestinal microflora of monkeys, normal and in pathology, and its correction by preparations of live bacteria from human biocenosis (coli bacteria, bifikol and bifidum bacterin)].

The study of the qualitative and quantitative composition of intestinal microflora in 15 anthropoid apes, 60 lower primates and 72 monkeys with clinically pronounced dysbacteriosis was made, which revealed the prevalence of microorganisms belonging to the genus Proteus, a decrease in the biological activity of normal Escherichia coli and in the content of bifido- and lactobacteria. The treatment of 39 rhesus and pig-tailed macaques with the preparations of live bacteria occurring in normal human microflora led to clinical convalescence and the normalization of the bacteriocenosis, while in 33 control animals no positive shifts in clinical and bacteriological data were observed. The essential similarity of the composition of intestinal microflora in higher and lower primates and in man makes it possible to use these animals as models for testing the effectiveness of new biological preparations and determines the expediency of using bacterial therapy for the treatment of monkeys at the period of acclimatization.

Animals↗
PubMed1981

[Articular infections in adults. Peripheral and vertebral involvement with common bacteria and tubercle bacteria].

2,166 cases of joint infection in adults were reviewed during a national inquiry. The peripheral infections due to common germs (1,080 cases) and tubercle bacilli (260 cases) were characterised by their frequency after the age of 60, the role of corticotherapy in onset of the infection and the predominance of staphylococci (60%) in pyogenic infections, the low proportion of deaths (4%) and the necessity of early treatment to observe better functional results. The vertebral lesions due to common bacteria (491 cases) were mainly localised in the lumbar regions (70%) whereas tuberculous infections (335 cases) usually affect the lower dorsal vertebrae (50%). Neurological signs and abscess were more frequent during tuberculous involvement. Needle puncture of the vertebral focus should be recommended owing to its help in etiological diagnosis. A cure was generally obtained without operation in the form of complete or incomplete block, this appearance is, however, less frequent than radiological signs of fixed osteolysis. The mortality is just as low as in peripheral infections.

Adolescent↗
PubMed1975

[The occurrence of listeria encephalitis in cattle in a loose housing after the use of litter, infected with listeria bacteria, from a broiler farm. To what extent do listeria bacteria occur in the gut contents of broilers (author's transl)].

In a loose housing, four cows had to be slaughtered as an emergency measure within a few weeks because of symptoms of encephalitis. Listeria monocytogenes of type 4 b were isolated both from the brains of these cows and from the litter previously spread in the cow stables, which was obtained from a broiler farm. At the same time an investigation of the occurrence of Listeria bacteria in the faeces/gut contents of broilers was undertaken. From the contents of 2373 intestines, representing 0.1 per cent of about 2,300,000 broilers from 146 farms, Listeria monocytogenes were isolated in 4.1 per cent of the birds. The infection occurred on six broiler farms, two of them exhibited recidivation. Listeria monocytogenes of type 4 b were involved three times, type 1 was concerned on two farms, and one strain could not be typed.

Animals↗