Abstract:
:In this report we describe the functional expression of EmrE, a 110-amino-acid multidrug transporter from Escherichia coli, in the yeast Saccharomyces cerevisiae. To allow for phenotypic complementation, a mutant strain sensitive to a series of cationic lipophilic drugs was first identified. A hemagglutinin epitope-tagged version of EmrE (HA-EmrE) conferring resistance to a wide variety of drugs, including acriflavine, ethidium, methyl viologen, and the neurotoxin 1-methyl-4-phenylpyridinium (MPP+), was functionally expressed in this strain. HA-EmrE is expressed in yeast at relatively high levels (0.5 mg/liter), is soluble in a mixture of organic solvents, and can be functionally reconstituted in proteoliposomes. In bacterial cells, EmrE removes toxic compounds by active transport through the plasma membrane, lowering their cytosolic concentration. However, yeast cells expressing HA-EmrE take up 14C-methyl viologen as well as control cells do. Thus, we investigated the basis of the enhanced resistance to the above compounds. Using Cu2+ ions or methylamine, we could selectively permeabilize the plasma membrane or deplete the proton electrochemical gradients across the vacuolar membrane, respectively. Incubation of yeast cells with copper ions caused an increase in 14C-methyl viologen uptake. In contrast, treatment with methylamine markedly diminished the extent of uptake. Conversely, the effect of Cu2+ and methylamine on a plasma membrane uptake system, proline, was essentially the opposite: while inhibited by the addition of Cu2+, it remained unaffected when cells were treated with methylamine. To examine the intracellular distribution of HA-EmrE, a functional chimera between HA-EmrE and the green fluorescent protein (HA-EmrE-GFP) was prepared. The pattern of HA-EmrE-GFP fluorescence distribution was virtually identical to that of the vacuolar marker FM 4-64, indicating that the transporter is found mainly in this organelle. Therefore, HA-EmrE protects yeast cells by lowering the cytoplasmic concentrations through removal of the toxin to the vacuole. This novel way of detoxification has been previously suggested to function in organisms in which a large vacuolar compartment exists. This report represents the first molecular description of such a mechanism.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
Yelin R,Rotem D,Schuldiner Sdoi
10.1128/JB.181.3.949-956.1999subject
Has Abstractpub_date
1999-02-01 00:00:00pages
949-56issue
3eissn
0021-9193issn
1098-5530journal_volume
181pub_type
杂志文章abstract::A ubiquinone-deficient mutant, carrying mutations in two genes affecting ubiquinone biosynthesis, has been used, in comparison with a normal strain, to determine the sequence of some of the components of the electron transport chain of Escherichia coli. The amounts of cytochromes reduced during aerobic steady-state co...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.133.2.477-484.1978
更新日期:1978-02-01 00:00:00
abstract::Con minus mutants, conjugation-defective mutants of Escherichia coli K-12, have been shown to be tolerant to colicins K and L. They map at approximately 14 min on the genetic map. The significance of the colicin tolerance of conjugation-defective mutants is discussed. ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.123.1.372-373.1975
更新日期:1975-07-01 00:00:00
abstract::The regulatory system that controls the expression of the Ti plasmid-borne octopine degradation (uad) and transfer (tra) genes in Agrobacterium tumefaciens was studied. A deletion mutant derived from the cointegrate plasmid R702::Ti-B6S3 was isolated, which was compatible with a wild-type Ti plasmid and which had reta...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.139.2.424-431.1979
更新日期:1979-08-01 00:00:00
abstract::Birnbaum, Jerome (University of Cincinnati, Cincinnati, Ohio), and Herman C. Lichstein. Metabolism of biotin and analogues of biotin by microorganisms. IV. Degradation of biotin, oxybiotin, and desthiobiotin by Lactobacillus casei. J. Bacteriol. 92:925-930. 1966.-Lactobacillus casei degrades biotin when it is present ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.92.4.925-930.1966
更新日期:1966-10-01 00:00:00
abstract::Induction of nod genes in Rhizobium and Bradyrhizobium species is dependent on the presence of plant-produced flavonoids, the NodD protein, and the cis-acting nod box promoter sequence. Although the nodD (nodD1) gene in Rhizobium species is constitutively expressed, nodD1 expression in Bradyrhizobium japonicum is indu...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.173.11.3356-3365.1991
更新日期:1991-06-01 00:00:00
abstract::An assay was developed to determine the amount of cyanophycin granules in blue-green algae. The amount of this polypeptide in cells of Anabaena cylindrica was measured as a function of culture age and was compared with changes in other proteinaceous cellular components. The data presented support the notion that the c...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.114.3.1213-1216.1973
更新日期:1973-06-01 00:00:00
abstract::The bdr (Borrelia direct repeat) gene family of the genus Borrelia encodes a polymorphic group of proteins that carry a central repeat motif region containing putative phosphorylation sites and a hydrophobic carboxyl-terminal domain. It has been postulated that the Bdr proteins may anchor to the inner membrane via the...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.182.15.4222-4226.2000
更新日期:2000-08-01 00:00:00
abstract::In a glycerol auxotroph of Staphylococcus aureus, the deprivation of glycerol affected the formation of certain membrane components. (i) There was synthesis of fatty acids at the predeprivation rate even though the fatty acids synthesized accumulated as free fatty acids rather than as esterified fatty acids; (ii) ther...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.112.1.413-420.1972
更新日期:1972-10-01 00:00:00
abstract::Bacteria form communities, termed biofilms, in which cells adhere to each other within a matrix, typically comprised of polysaccharides, proteins, and extracellular DNA. Biofilm formation by the marine bacterium Vibrio fischeri requires the Syp polysaccharide, but the involvement of matrix proteins is as yet unknown. ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.02292-14
更新日期:2015-02-01 00:00:00
abstract::Two activites causing nitrite disappearance are found in extracts of Neurospora; one, inducible by nitrate or nitrite and present only in nitrite-utilizing strains, catalyze the stoichiometric reduction of nitrite to ammonia; the other, present in all strains under all conditions, causes the disappearance of nitrite t...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.123.2.755-758.1975
更新日期:1975-08-01 00:00:00
abstract::Paenibacillus mucilaginosus is a ubiquitous functional bacterium in microbial fertilizer. Here we report the complete sequence of P. mucilaginosus 3016. Multiple sets of functional genes have been found in the genome. To the best of our knowledge, this is the first announcement about the complete genome sequence of a ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00323-12
更新日期:2012-05-01 00:00:00
abstract::No catalase activity was detected in four strains of glucose-grown Mycoplasma pneumoniae at any time during the replication of the organism. Exogenous catalase dramatically increased the O(2) uptake with glycerol, presumably by releasing inhibition caused by hydrogen peroxide. The effect of added catalase on the O(2) ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.95.4.1425-1430.1968
更新日期:1968-04-01 00:00:00
abstract::When Methanobacterium thermoautotrophicum cells were incubated in 50 mM potassium phosphate buffer (pH 7.0) containing 1 M sucrose and autolysate from Methanobacterium wolfei, they were transformed into protoplasts. The protoplasts, which possessed no cell wall, lysed in buffer without sucrose. Unlike whole cells, the...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.168.2.892-900.1986
更新日期:1986-11-01 00:00:00
abstract::The homotrimeric enzyme Mt-Cam from Methanosarcina thermophila is the archetype of the gamma class of carbonic anhydrases. A search of databases queried with Mt-Cam revealed that a majority of the homologs comprise a putative subclass (CamH) in which there is major conservation of all of the residues essential for the...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01164-09
更新日期:2010-03-01 00:00:00
abstract::In previous work, we characterized the bases in an iteron of plasmid R6K that are important for the binding of pi protein monomers and dimers. Here we investigate the following six amino acids of pi, encoded by pir, hypothesized to be important for DNA contact: Ser71, Try74, Gly131, Gly211, Arg225, and Arg254. ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00109-07
更新日期:2007-07-01 00:00:00
abstract::Agrobacterium rhizogenes strain 15834, which incites hairy root disease in plants, harbors three large plasmids: pAr15834a (107 x 10(6) daltons), pAr15834b (154 x 10(6) daltons), and pAr15834c (258 x 10(6) daltons). Kanamycin-resistant transconjugants were selected in a cross of kanamycin-resistant derivate of strain ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.141.3.1134-1141.1980
更新日期:1980-03-01 00:00:00
abstract::When cells of two auxotrophic mutants of Sulfolobus acidocaldarius are mixed and incubated on solid medium, they form stable genetic recombinants which can be selected, enumerated, and characterized. Any of a variety of auxotrophic markers can recombine with each other, and the phenomenon has been observed at temperat...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.178.11.3207-3211.1996
更新日期:1996-06-01 00:00:00
abstract::Onoue, Kaoru, (Kyushu University, Fukuoka, Japan), Masayasu Kitagawa, and Yuichi Yamamura. Chemical studies on cellular components of Bordetella pertussis. I. Purification and properties of agglutinogen. J. Bacteriol. 82:648-656. 1961.-A method is described for the preparation of the agglutinogen of Hemophilus pertuss...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.82.5.648-656.1961
更新日期:1961-11-01 00:00:00
abstract::The role of the carboxy terminus of the Escherichia coli cell division protein FtsA in bacterial division has been studied by making a series of short sequential deletions spanning from residue 394 to 420. Deletions as short as 5 residues destroy the biological function of the protein. Residue W415 is essential for th...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.182.22.6366-6373.2000
更新日期:2000-11-01 00:00:00
abstract::The regulation of the asparagine synthetase A gene of Escherichia coli was studied in vitro with a coupled transcription-translation system. It was shown that the 17-kilodalton gene, which is transcribed divergently from the adjacent asnA gene, codes for an activator of asnA transcription. The synthesis of the 17-kilo...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.164.1.310-315.1985
更新日期:1985-10-01 00:00:00
abstract::After thermal denaturation, an in vivo-labeled RNA was found in a temperature-sensitive initiation mutant of Bacillus subtilis (dna-37) associated with high-molecular-weight DNA. This RNA could be clearly distinguished from other RNA species by different techniques of separation, such as Sepharose 2B filtration, chrom...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.149.1.79-91.1982
更新日期:1982-01-01 00:00:00
abstract::Strains of avian pathogenic Escherichia coli (APEC), the common pathogen of avian colibacillosis, encounter reactive oxygen species (ROS) during the infection process. Superoxide dismutases (SODs), acting as antioxidant factors, can protect against ROS-mediated host defenses. Our previous reports showed that the sodA ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00625-18
更新日期:2019-02-25 00:00:00
abstract::Entomopathogenic bacteria of the genus Photorhabdus harbor a type III secretion system. This system was probably acquired prior to the separation of the species within this genus. Furthermore, the core components of the secretion machinery are highly conserved but the predicted effectors differ between Photorhabdus lu...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.186.13.4376-4381.2004
更新日期:2004-07-01 00:00:00
abstract::A Rhodobacter capsulatus hemC mutant has been isolated and used to show that oxygen regulates the intracellular levels of porphobilinogen. Experiments using a hemB-cat gene fusion demonstrated that oxygen does not transcriptionally regulate hemB transcription. Porphobilinogen synthase activity is not regulated by oxyg...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.184.6.1685-1692.2002
更新日期:2002-03-01 00:00:00
abstract::We used primer extension and mutational analysis to identify a promoter upstream of ilvB, the first gene in the ilv-leu operon of Bacillus subtilis. Between the promoter and ilvB, there is a 482-bp leader region which contains a sequence that resembles a factor-independent transcription terminator. In in vitro transcr...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.174.10.3212-3219.1992
更新日期:1992-05-01 00:00:00
abstract::Gene amplifications have been detected as a transitory phenomenon in bacterial cultures. They are predicted to contribute to rapid adaptation by simultaneously increasing the expression of genes clustered on the chromosome. However, genome amplifications have rarely been described in natural isolates. Through DNA arra...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01357-07
更新日期:2008-01-01 00:00:00
abstract::We have isolated a mutant of Pseudomonas aeruginosa deficient in fructose 1,6-bisphosphate aldolase activity. This mutant, similar to the mutants deficient in any of the Entner-Doudoroff pathway enzymes, does not allow appreciable alginate formation from glucose and gluconate, but allows alginate synthesis from mannit...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.161.1.458-460.1985
更新日期:1985-01-01 00:00:00
abstract:UNLABELLED:It is well established that the RpoN-RpoS sigma factor (σ(54)-σ(S)) cascade plays an essential role in differential gene expression during the enzootic cycle of Borrelia burgdorferi, the causative agent of Lyme disease. The RpoN-RpoS pathway is activated by the response regulator/σ(54)-dependent activator (a...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01010-15
更新日期:2016-04-28 00:00:00
abstract::Mir M7 is a spontaneous morphologically conditional mutant of Klebsiella pneumoniae which grows as round cells (cocci) at pH 7 and as normal rods at pH 5.8. We studied the rates of peptidoglycan synthesis of cocci and rods growing at pH values of 7 and 5.8, respectively. It was found that exponentially growing cocci p...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.137.2.727-734.1979
更新日期:1979-02-01 00:00:00
abstract::A mutant of Escherichia coli is described which is defective in the conversion of arginine to putrescine. The activity of the enzyme agmatine ureohydrolase is greatly reduced, whereas the activity of the other two enzymes of the pathway, the constitutive arginine decarboxylase and the inducible arginine decarboxylase,...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.101.3.725-730.1970
更新日期:1970-03-01 00:00:00