Abstract:
:Laccases couple the oxidation of phenolic compounds to the reduction of molecular oxygen and thus span a wide variety of applications. While laccases of eukaryotes and bacteria are well characterized, these enzymes have not been described in archaea. Here, we report the purification and characterization of a laccase (LccA) from the halophilic archaeon Haloferax volcanii. LccA was secreted at high levels into the culture supernatant of a recombinant H. volcanii strain, with peak activity (170 +/- 10 mU.ml(-)(1)) at stationary phase (72 to 80 h). LccA was purified 13-fold to an overall yield of 72% and a specific activity of 29.4 U.mg(-)(1) with an absorbance spectrum typical of blue multicopper oxidases. The mature LccA was processed to expose an N-terminal Ala after the removal of 31 amino acid residues and was glycosylated to 6.9% carbohydrate content. Purified LccA oxidized a variety of organic substrates, including bilirubin, syringaldazine (SGZ), 2,2,-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and dimethoxyphenol (DMP), with DMP oxidation requiring the addition of CuSO(4). Optimal oxidation of ABTS and SGZ was at 45 degrees C and pH 6 and pH 8.4, respectively. The apparent K(m) values for SGZ, bilirubin, and ABTS were 35, 236, and 670 muM, with corresponding k(cat) values of 22, 29, and 10 s(-)(1), respectively. The purified LccA was tolerant of high salt, mixed organosolvents, and high temperatures, with a half-life of inactivation at 50 degrees C of 31.5 h.
journal_name
Appl Environ Microbioljournal_title
Applied and environmental microbiologyauthors
Uthandi S,Saad B,Humbard MA,Maupin-Furlow JAdoi
10.1128/AEM.01757-09subject
Has Abstractpub_date
2010-02-01 00:00:00pages
733-43issue
3eissn
0099-2240issn
1098-5336pii
AEM.01757-09journal_volume
76pub_type
杂志文章abstract::Selenoprotein synthesis in Escherichia coli strictly depends on the presence of a specific selenocysteine insertion sequence (SECIS) following the selenocysteine-encoding UGA codon of the respective mRNA. It is recognized by the selenocysteine-specific elongation factor SelB, leading to cotranslational insertion of se...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02238-07
更新日期:2008-03-01 00:00:00
abstract::Species diversity, phylogenetic affiliations, and environmental occurrence patterns of thiosulfate-oxidizing marine bacteria were investigated by using new isolates from serially diluted continental slope and deep-sea abyssal plain sediments collected off the coast of New England and strains cultured previously from G...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.66.8.3125-3133.2000
更新日期:2000-08-01 00:00:00
abstract::Rates of dissolved inorganic carbon (DIC), formate, and acetate mineralization and/or assimilation were determined in 13 high-temperature (>73 °C) hot springs in Yellowstone National Park (YNP), Wyoming, in order to evaluate the relative importance of these substrates in supporting microbial metabolism. While 9 of the...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00511-15
更新日期:2015-06-01 00:00:00
abstract::A total of 69 dyes were incorporated separately at different concentrations into an agar medium for evaluation of their effects on the quantitative recovery of five serotypes of Yersinia enterocolitica. One strain of Pseudomonas aeruginosa and one strain of Bacillus cereus were included for comparative purposes. Certa...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.38.2.205-211.1979
更新日期:1979-08-01 00:00:00
abstract::The alpha-galactosidase gene (aga) and a gene coding for a putative transcriptional regulator from the LacI/GalR family (galR) of Lactococcus raffinolactis ATCC 43920 were cloned and sequenced. When transferred into Lactococcus lactis and Pediococcus acidilactici strains, aga modified the sugar fermentation profile of...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.68.12.6152-6161.2002
更新日期:2002-12-01 00:00:00
abstract::Erwinia carotovora subsp. atroseptica, E. carotovora subsp. betavasculorum, and E. carotovora subsp. carotovora produce high levels of extracellular enzymes, such as pectate lyase (Pel), polygalacturonase (Peh), cellulase (Cel), and protease (Prt), and the quorum-sensing signal N-acyl-homoserine lactone (AHL) at 28 de...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.71.8.4655-4663.2005
更新日期:2005-08-01 00:00:00
abstract::The uncultivated bacterial endosymbionts of the hydrothermal vent tubeworm Riftia pachyptila play a central role in providing their host with fixed carbon. While this intimate association between host and symbiont indicates tight integration and coordination of function via cellular communication mechanisms, no such s...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.63.9.3494-3498.1997
更新日期:1997-09-01 00:00:00
abstract::The bile salt hydrolase activity in intestinal homogenates reflects composite activities of the gastrointestinal microbial consortia. We have proposed that specific transformations of conjugated bile acids by the intestinal microflora result in the production of metabolites which depress the growth of poultry. The inf...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.54.2.337-342.1988
更新日期:1988-02-01 00:00:00
abstract::Respiration rates of bacterial cultures can be a powerful tool in gauging the effects of genetic manipulation and environmental changes affecting overall metabolism. We present an optical method for measuring respiration rates using a robust phosphorescence lifetime-based sensor and off-the-shelf technology. This meth...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.72.2.1692-1695.2006
更新日期:2006-02-01 00:00:00
abstract::Secondary sewage effluent containing about 3 X 10(4) plaque-forming units of polio virus type 1 (LSc) per ml was passed through columns 250 cm in length packed with calcareous sand from an area in the Salt River bed used for ground-water recharge of secondary sewage effluent. Viruses were not detected in 1-ml samples ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.32.4.520-526.1976
更新日期:1976-10-01 00:00:00
abstract::We investigated the molecular relationship between the 60-megadalton (Mdal) recombinant lactose plasmids in ML 3 x LM2301 lactose-positive (Lac+) transconjugants and the genetic material of Streptococcus lactis ML3. Lactose metabolism is linked to the 33-Mdal plasmid pSK08 in ML3, and the recipient LM2301 is cured of ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.43.5.1006-1010.1982
更新日期:1982-05-01 00:00:00
abstract::The importance of viruses in aquatic ecosystem functioning has been widely described. However, few studies have examined tropical aquatic ecosystems. Here, we evaluated for the first time viruses and their relationship with other planktonic communities in an Amazonian freshwater ecosystem. Coupling between viruses and...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.01161-10
更新日期:2010-11-01 00:00:00
abstract::Waters in marine and freshwater areas of Puerto Rico were analyzed for the presence of Legionella spp. by direct fluorescent antibody assay with guinea pig confirmation. Several species, including L. bozemanii, L. dumoffii, L. gormanii, L. longbeachae, L. micdadei, and L. pneumophila, were widely distributed among all...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.53.9.2231-2236.1987
更新日期:1987-09-01 00:00:00
abstract::Conjugal transfer of lactose-fermenting ability (Lac+), nisin resistance (Nisr), and phage resistance (Hsp+) was demonstrated in matings between Streptococcus lactis ME2 (donor) and Streptococcus cremoris M43a (recipient), a derivative of M12R. Transconjugants were detected by transfer of Lac+ and were found to exhibi...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.50.4.851-858.1985
更新日期:1985-10-01 00:00:00
abstract::Anaerobic degradation of 2-methylnaphthalene was investigated with a sulfate-reducing enrichment culture. Metabolite analyses revealed two groups of degradation products. The first group comprised two succinic acid adducts which were identified as naphthyl-2-methyl-succinic acid and naphthyl-2-methylene-succinic acid ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.66.12.5329-5333.2000
更新日期:2000-12-01 00:00:00
abstract::Xylanase activity from naturally occurring color variants of Aureobasidium pullulans was associated with extracellular monomeric proteins of 20 to 21 kilodaltons. Xylanase represented nearly half the total extracellular protein, with a yield of up to 0.3 g of xylanase per liter. The specific activity of partially puri...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.52.5.1026-1030.1986
更新日期:1986-11-01 00:00:00
abstract::Desulfitobacterium hafniense strain TCE1 is capable of metabolically reducing tetra- and trichloroethenes by organohalide respiration. A previous study revealed that the pce gene cluster responsible for this process is located on an active composite transposon, Tn-Dha1. In the present work, we investigated the effects...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.01221-12
更新日期:2012-09-01 00:00:00
abstract::Heterocystous filamentous cyanobacterium Anabaena cylindrica B629 and nonheterocystous filamentous cyanobacterium Oscillatoria sp. strain Miami BG7 were cultured in media with N(2) as the sole nitrogen source; and activities of oxygen-dependent hydrogen uptake, photohydrogen production, photooxygen evolution, and resp...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.50.2.287-291.1985
更新日期:1985-08-01 00:00:00
abstract::Photorhabdus luminescens is a bacterium which is mutualistic with entomophagous nematodes and which secretes high-molecular-weight toxin complexes following its release into the insect hemocoel upon nematode invasion. Thus, unlike other protein toxins from Bacillus thuringiensis (delta-endotoxins and Vip's), P. lumine...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.64.8.3036-3041.1998
更新日期:1998-08-01 00:00:00
abstract::Marine microbial communities often contain multiple closely related phylogenetic clades, but in many cases, it is still unclear what physiological traits differentiate these putative ecotypes. The numerically abundant marine cyanobacterium Synechococcus can be divided into at least 14 clades. In order to better unders...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00358-06
更新日期:2006-11-01 00:00:00
abstract::Thirty-three standard mycotoxins were assayed by thin-layer chromatography and by cytotoxicity in HEp-2 and Chang cells. Various levels of detection were found. The cytotoxicity test was significantly more sensitive than thin-layer chromatography for the trichothecenes and should be useful for screening extracts from ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.46.4.948-950.1983
更新日期:1983-10-01 00:00:00
abstract::LeLoir glycosyltransferases are important biocatalysts for the production of glycosidic bonds in natural products, chiral building blocks, and pharmaceuticals. Trehalose transferase (TreT) is of particular interest since it catalyzes the stereo- and enantioselective α,α-(1→1) coupling of a nucleotide sugar donor and m...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.03084-18
更新日期:2019-04-04 00:00:00
abstract::Molecular tools that can provide an estimate of the in situ growth rate of Geobacter species could improve understanding of dissimilatory metal reduction in a diversity of environments. Whole-genome microarray analyses of a subsurface isolate of Geobacter uraniireducens, grown under a variety of conditions, identified...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.03263-12
更新日期:2013-03-01 00:00:00
abstract::Each year, thousands of new protistan 18S rRNA sequences are detected in environmental samples. Many of these sequences are molecular signatures of new protistan species, classes, and/or kingdoms that have never been seen before. The main goal of this study was to enable visualization of these novel organisms and to c...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.69.11.6856-6863.2003
更新日期:2003-11-01 00:00:00
abstract::Lactase (beta-d-galactosidase) was produced by Candida pseudotropicalis grown in deproteinized whey. Maximum enzyme production in 2% whey was obtained by supplementation with 0.15% yeast extract, 0.1% (NH(4))(2)SO(4), and 0.05% KH(2)PO(4) (wt/vol). Highest enzyme values (4.35 U/mg of cells and 68 U/ml) were obtained w...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.37.6.1201-1205.1979
更新日期:1979-06-01 00:00:00
abstract::We previously published a genetic map of Gibberella zeae (Fusarium graminearum sensu lato) based on a cross between Kansas strain Z-3639 (lineage 7) and Japanese strain R-5470 (lineage 6). In this study, that genetic map was aligned with the third assembly of the genomic sequence of G. zeae strain PH-1 (lineage 7) usi...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.01866-07
更新日期:2008-04-01 00:00:00
abstract::Previously isolated dissimilatory perchlorate-reducing bacteria (DPRB) have been primarily affiliated with the Betaproteobacteria. Enrichments from the cathodic chamber of a bioelectrical reactor (BER) inoculated from creek water in Berkeley, CA, yielded a novel organism most closely related to a previously described ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00015-10
更新日期:2010-07-01 00:00:00
abstract::The crenarchaeon Sulfolobus acidocaldarius has been described to synthesize trehalose via the maltooligosyltrehalose synthase (TreY) and maltooligosyltrehalose trehalohydrolase (TreZ) pathway, and the trehalose glycosyltransferring synthase (TreT) pathway has been predicted. Deletion mutant analysis of strains with si...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.01565-20
更新日期:2020-11-24 00:00:00
abstract::Methanogenic bacteria, which are presently identified on the basis of cell morphology and substrate conversion to CH(4), can be differentiated from nonmethanogens and identified in pure or mixed culture on the basis of their autofluorescence under ultraviolet illumination. ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.33.3.713-717.1977
更新日期:1977-03-01 00:00:00
abstract::Seven organotin compounds and tin chloride were tested for their effects on the methanogenic bacteria Methanococcus thermolithotrophicus, Methanococcus deltae delta LH, and Methanosarcina barkeri 227. The methanogens were strongly inhibited by triethyltin, tripropyltin, and monophenyltin compounds, generally at concen...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.57.4.1189-1193.1991
更新日期:1991-04-01 00:00:00