Abstract：
:Amino acid residues in the active site of quinoline 2-oxidoreductase (Qor) that are deemed important for substrate binding and turnover were replaced by site-directed mutagenesis. The apparent k(cat) values for quinoline were reduced 2.4-, 38-, 40-, and 199-fold in the protein variants QorA259G, QorW331G, QorV373A, and QorA546G, respectively. The substitution A259G did not significantly alter K(m app). Despite the presumed crucial role of W331 and V373 in substrate positioning, the replacements W331G (K(m app): 0.33 mM) and V373A (K(m app): 0.41 mM) only slightly affected affinity for quinoline (K(m app) of Qor: 0.12 mM). QorA546G showed an increased affinity for quinoline and quinoxaline, as suggested by its 4.3- and 7.5-fold decrease in K(m) (app (quinoline))and K(m app (quinoxaline)), respectively, compared with Qor. The relative activities of the protein variants towards substituted quinolines differed from those of Qor. QorW331G, for example, may be suitable for hydroxylation of quinoxaline and C4-substituted quinolines.
journal_name
Curr Microbioljournal_title
Current microbiologyauthors
Purvanov V,Fetzner Sdoi
10.1007/s00284-004-4452-ykeywords:
subject
Has Abstractpub_date
2005-04-01 00:00:00pages
217-22issue
4eissn
0343-8651issn
1432-0991journal_volume
50pub_type
杂志文章abstract：:Ruminal proteolysis and subsequent amino acid degradation represent considerable economic loss in ruminant production. The hyper ammonia-producing bacteria (HAB) are largely responsible for amino acid deamination in the rumen. HAB can be controlled with ionophores, but they are also susceptible to antimicrobial plant ...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-010-9586-5
更新日期：2010-08-01 00:00:00
abstract：:Cutaneous fungal infections are common and widespread. Antifungal agents used for the treatment of these infections often have undesirable side effects. Furthermore, increased resistance of the microorganisms to the antifungal drugs becomes the growing problem. Accordingly, the search for natural antifungal compounds ...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-014-0585-9
更新日期：2014-09-01 00:00:00
abstract：:Plasmids play a central role in engineering recombinant bacteria because they are the primary vehicles used to manipulate targeted sequences. In some cases, bacteria of interest are poorly provided with suitable tools for these molecular or genetic manipulations. In this context, we constructed from two shuttle clonin...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-006-0358-1
更新日期：2007-05-01 00:00:00
abstract：:Rhizobium sp. SIN-1, a nitrogen-fixing symbiont of Sesbania aculeata and other tropical legumes, carries two copies of nodD, both on a sym plasmid. We have isolated these two nodD genes by screening a genomic library of Rhizobium sp. SIN-1 with a nodD probe from Sinorhizobium meliloti. Nucleotide sequence and the dedu...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-002-3772-z
更新日期：2002-11-01 00:00:00
abstract：:A bacterium that tested positive with antibodies specific for Escherichia coli O157 was isolated from beef during routine screening procedures. The bacterium was identified as E. fergusonii by biochemical testing and partial sequencing of 16S rRNA. The isolate was tested for the presence of genes encoding Shiga toxins...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-005-0447-6
更新日期：2006-06-01 00:00:00
abstract：:We develop a method to capture marine bacterial strains at high efficiency to replace the conventional two-step collecting method. Lab-made, Fe3O4 magnetic beads were used to firstly verify the feasibility of capture in artificial seawater, using Bacillus velezensis. Almost 100% of the bacteria could be captured and s...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-020-01923-6
更新日期：2020-07-01 00:00:00
abstract：:This paper presents the results of studies on the activity of extra-cellular enzymes in soil-willow vegetation filter soil which is used in the post-treatment of household sewage in an onsite wastewater treatment system located in central Poland. Wastewater is discharged from the detached house by gravity into the ons...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-012-0230-4
更新日期：2012-12-01 00:00:00
abstract：:In laboratory cultures of ice nucleation-active (Ice+) Erwinia herbicola isolates, it has been difficult to achieve high-level expression of ice nuclei, especially nuclei active at temperatures warmer than -5 degrees C (i.e., type 1 ice nuclei). Here we demonstrate that starvation for phosphate and exposure to low tem...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s002849900325
更新日期：1998-06-01 00:00:00
abstract：:Lake Elmenteita is one of the alkaline saline lakes within the Kenyan Rift valley. The lake is situated on the floor of the Kenyan Rift Valley at 1,776 m above sea level and has no direct outlet. The microbial diversity of the lake was investigated using a culture-independent approach. Five different sampling points w...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-010-9692-4
更新日期：2011-01-01 00:00:00
abstract：:pH affected significantly the growth and the glucose fermentation pattern of Propionibacterium microaerophilum. In neutral conditions (pH 6.5-7.5), growth and glucose fermentation rate (qs) were optimum producing propionate, acetate, CO(2), and formate [which together represented 90% (wt/wt) of the end products], and ...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-002-3839-x
更新日期：2003-02-01 00:00:00
abstract：:The duodenal ulcer promoting gene (dupA), located in the plasticity region of Helicobacter pylori (H. pylori), is predicted to form a type IV secretory system (T4SS) with vir genes around dupA. In the study, we investigated the association between the dupA cluster status and the virulence of H. pylori in a littoral re...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-015-0812-z
更新日期：2015-07-01 00:00:00
abstract：:We constructed recombinant phage particles displaying the Bacillus thuringiensis Cry1Ba4 active toxin using the pfUSE5 and pComb3X phagemid vectors. The recombinant phage particles were screened and evaluated for displayed biologically active Cry1Ba4 toxin against the target insect larvae. Concurrent expression of Cry...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-006-0164-9
更新日期：2006-11-01 00:00:00
abstract：:In the present study, probiotic, safety and functional characteristics of eight indigenous bifidobacterial isolates were compared to identify suitable strains for functional food application. Among the isolates, six strains of Bifidobacterium longum and one each of Bifidobacterium breve and Bifidobacterium bifidum wer...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-018-1615-9
更新日期：2019-03-01 00:00:00
abstract：:The ability of Burkholderia sp. VUN10013 to degrade anthracene in microcosms of two acidic Thai soils was studied. The addition of Burkholderia sp. VUN10013 (initial concentration of 10(5) cells g(-1) dry soil) to autoclaved soil collected from the Plew District, Chanthaburi Province, Thailand, supplemented with anthr...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-008-9157-1
更新日期：2008-08-01 00:00:00
abstract：:Culture-based analysis was employed in parallel with PCR amplification of 16S rDNA, coupled with denaturing gradient gel electrophoresis (DGGE), to profile bacterial species associated with different developmental stages of the pine false webworm (PFW), Acantholyda erythrocephala, a sawfly pest responsible for inciden...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-008-9243-4
更新日期：2008-12-01 00:00:00
abstract：:Although neutral mine drainage is the less frequent subject of the interest than acid mine drainage, it can have adverse environmental effects caused mainly by precipitation of dissolved Fe. The aim of the study was to characterize the composition of bacterial population in environment with high concentration of iron ...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-018-1472-6
更新日期：2018-08-01 00:00:00
abstract：:A novel Gram-negative gamma-proteobacterium, non-sporulating motile, rod or coccus-shaped bacterium designated as strain PKS7T was isolated from a sediment sample collected from Chilika Lake, Odisha, India and characterized taxonomically using a polyphasic approach. The major quinone was Q8 and major cellular fatty ac...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-019-01802-9
更新日期：2020-01-01 00:00:00
abstract：:Production of pediocin in Pediococcus acidilactici is associated with pMBR1.0, which encodes prepediocin, a pediocin immunity protein, and two proteins involved in secretion and precursor processing. These four genes are organized as an operon under control of a single promoter. We have constructed shuttle vectors tha...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s002849900462
更新日期：1999-11-01 00:00:00
abstract：:The expression of the eukaryotic bbc1 (breast basic conserved) gene (the bbc1 gene of the marine green alga Chlamydomonas sp. W-80 strain) enhanced the tolerance against salt-stress and freezing-stress in E. coli cells. The expression of the BBC1 protein in the E. coli cells carrying the algal bbc1 gene and that in th...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s002840010199
更新日期：2001-03-01 00:00:00
abstract：:The great increase in the abundance and phylogenetic diversity of Flavobacterium spp. within a few hundred meters downstream of the discharge site of the Westerhöfer Bach, a hardwater rivulet, raised the question whether adjacent soil may serve as a reservoir of bacteria not detected in discharge water. To address thi...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-008-9323-5
更新日期：2009-05-01 00:00:00
abstract：:Growth on aniline by three purple non-sulfur bacteria (Rhodospirillum rubrum ATCC 11170, Rhodobacter sphaeroides DSM 158, and Rubrivivax benzoatiliticus JA2) as nitrogen, or carbon source could not be demonstrated. However in its presence, production of indole derivatives was observed with all the strains tested. At l...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-010-9609-2
更新日期：2010-10-01 00:00:00
abstract：:The Helicobacter pylori extra gastric reservoir is probably the oral cavity. In order to evaluate the presence of this bacterium in patients with periodontitis and suspicious microbial cultures, saliva was collected from these and non-periodontitis subjects. PCRs targeting 16S rRNA gene and a 860 bp specific region we...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-014-0578-8
更新日期：2014-09-01 00:00:00
abstract：:We have shown previously that Spo0A approximately P-dependent sinIR operon expression was substantially down-regulated in abrB null mutant backgrounds. In this report, we show that loss of function mutations in abrB also cause phosphorelay gene expression to be down regulated. abrB null mutations caused diminished veg...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-003-4186-2
更新日期：2004-04-01 00:00:00
abstract：:Vibrio vulnificus, a highly virulent marine bacterium, is the causative agent of both serious wound infections and fatal septicemia in many areas of the word. A gene (hlyIII) encoding a hemolysin was cloned and sequenced from V. vulnificus. Nucleotide sequence analysis predicted an open reading frame of 642 bp encodin...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-004-4288-5
更新日期：2004-09-01 00:00:00
abstract：:Regulated secretory proteins are sorted via selective co-aggregation in eukaryotes. Cellobiase (C) of the filamentous fungus Termitomyces clypeatus remained co-aggregated with sucrase (S), and only one isoform of each of the enzymes was present in intra- and extracellular extracts. Kinetics of secretion of sucrase inc...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-001-7001-y
更新日期：2002-07-01 00:00:00
abstract：:Nine structurally similar macrolide antibiotics were tested at a concentration of 0.5 microg/ml for their relative inhibitory effects on ribosome functions in Staphylococcus aureus cells. Eight of the compounds examined inhibited protein synthesis at this concentration. Seven of the nine compounds were also effective ...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s002849900402
更新日期：1998-12-01 00:00:00
abstract：:Whole-crystal preparations from strains HD-1 and HD-133, activated Cry1Ab and Cry1C toxins as well as Cry1Aa, Cry1Ac, Cry1D, and Cry2Aa protoxins were tested for toxicity to 2nd-instar larvae of the diamondback moth, Plutella xylostella. Mortality data recorded after 2 and 5 days provided different results that were r...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s002849900438
更新日期：1999-09-01 00:00:00
abstract：:Bacillus thuringiensis strain BtMC28 was isolated from the soil sample in China. Two novel crystal protein genes were found by using the PCR-RFLP method. Moreover, the full-length sequences of two novel genes were obtained by a single oligonucleotide nested (SON)-PCR upstream and downstream strategy. Sequence analysis...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-009-9386-y
更新日期：2009-06-01 00:00:00
abstract：:The outer membrane protein of Photobacterium damsela (OMP-PD) and the gene encoding for this porin protein were isolated and characterized. The deduced amino acid sequence of the OMP-PD monomer has 338 amino acids and a calculated molecular weight of 36,951 Da. This sequence includes a 22-amino acid signal peptide at ...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-003-4111-8
更新日期：2004-03-01 00:00:00
abstract：:A novel leucine aminopeptidase was purified from a Bacillus thuringiensis israelensis (Bti) culture. The purification stages included heating the concentrated supernatant to 65 degrees C for 90 min, anion-exchange chromatography by DEAE cellulose, and hydrophobic chromatography by phenyl Sepharose. The specific activi...
journal_title：Current microbiology
pub_type： 杂志文章
doi：10.1007/s00284-007-9004-9
更新日期：2007-11-01 00:00:00
