Abstract:
:The ever-increasing industrial demand for biocatalysis necessitates innovations in the preparation and stabilization of biocatalysts. In this study, we demonstrated that beta-galactosidase (beta-Gal) displayed on Bacillus spores by fusion to the spore coat proteins (CotG) may be used as a whole-cell immobilized biocatalyst for transgalactosylation in water-solvent biphasic reaction systems. The resulting spores had a specific hydrolytic activity of 5 x 10(3) U/g (dry weight) of spores. The beta-Gal was tightly attached to the spore surface and was more stable in the presence of various organic solvents than its native form was. The thermostability of the spore-displayed enzyme was also increased, and the enzyme was further stabilized by chemically cross-linking it with glutaraldehyde. With spore-displayed beta-Gal, octyl-beta-D-galactopyranoside was synthesized at concentrations up to 27.7 mM (8.1 g/liter) with a conversion yield of 27.7% (wt/wt) after 24 h from 100 mM lactose and 100 mM octanol dissolved in phosphate buffer and ethyl ether, respectively. Interestingly, the spores were found to partition mainly at the interface between the water and solvent phases, and they were more available to catalysis between the two phases, as determined by light microscopy and confocal fluorescence microscopy. We propose that spore display not only offers a new and facile way to construct robust biocatalysts but also provides a novel basis for phase transfer biocatalytic processes.
journal_name
Appl Environ Microbioljournal_title
Applied and environmental microbiologyauthors
Kwon SJ,Jung HC,Pan JGdoi
10.1128/AEM.01489-06subject
Has Abstractpub_date
2007-04-01 00:00:00pages
2251-6issue
7eissn
0099-2240issn
1098-5336pii
AEM.01489-06journal_volume
73pub_type
杂志文章abstract::The genes encoding thermostable alpha- and beta-galactosidases from an extremely thermophilic bacterium, Thermus strain T2, were cloned in Escherichia coli. The alpha-galactosidase gene was located just downstream from the beta-galactosidase gene. The genes were introduced into Thermus thermophilus HB27 with the aid o...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.56.7.2251-2254.1990
更新日期:1990-07-01 00:00:00
abstract::The vaginal mucosa of ovariectomized female rats has been examined by scanning electron microscopy before and after estrogen [1,3,5(10)-estratriene-3,17beta-diol] treatment. Without estrogen stimulation vaginal colonization is minimal and the epithelium is characterized by a layer of epithelial cells covered with smal...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.34.1.80-87.1977
更新日期:1977-07-01 00:00:00
abstract::In all purification stages of a biological sewage treatment plant, phototrophic bacteria were detected by the method of viable cell counts. The predominant species identified belonged to the genus Rhodopseudomonas of purple nonsulfur bacteria. The number of phototrophic bacteria was highest in wastewater containing sl...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.35.1.38-44.1978
更新日期:1978-01-01 00:00:00
abstract::Enterobacteriaceae-associated blaCTX-M genes have become globally widespread within the past 30 years. Among isolates from Washington State cattle, Escherichia coli strains carrying blaCTX-M (CTX-M E. coli strains) were absent from a set of 2008 isolates but present in a set of isolates from 2011. On 30 Washington Sta...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00463-15
更新日期:2015-07-01 00:00:00
abstract::Inhibition of Aspergillus flavus growth from spores was used as a simple bioassay for toxicity of Al and Mn mobilized by simulated acid precipitation. Al was identified as being toxic in soil leachates resulting from acid inputs of pH less than 2.7. Inhibition by Mn was not detectable. The addition of fluoride signifi...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.46.3.758-761.1983
更新日期:1983-09-01 00:00:00
abstract::Accumulating evidence suggests that pesticides have played a role in the increased rate of honey bee colony loss. One of the most commonly used pesticides in the United States is the neonicotinoid imidacloprid. Although the primary mode of action of imidacloprid is on the insect nervous system, it has also been shown ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00545-18
更新日期:2018-06-18 00:00:00
abstract::Two different endoxylanases (1,4-beta-D-xylan xylanohydrolases, EC 3.2.1.8), designated 1 and 2, have been purified by column chromatography to apparent homogeneity from the nonsedimentable extracellular culture fluid of the strictly anaerobic, ruminal bacterium Fibrobacter succinogenes S85 grown on crystalline cellul...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.58.1.157-168.1992
更新日期:1992-01-01 00:00:00
abstract::The N-acetylglucosaminidase LytB of Streptococcus pneumoniae is involved in nasopharyngeal colonization and is responsible for cell separation at the end of cell division; thus, ΔlytB mutants form long chains of cells. This paper reports the construction and properties of a defective pneumococcal mutant producing an i...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00280-20
更新日期:2020-05-05 00:00:00
abstract::Saccharomyces cerevisiae normally cannot assimilate mannitol, a promising brown macroalgal carbon source for bioethanol production. The molecular basis of this inability remains unknown. We found that cells capable of assimilating mannitol arose spontaneously from wild-type S. cerevisiae during prolonged culture in ma...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02906-14
更新日期:2015-01-01 00:00:00
abstract::Four bacteria, Bacillus cereus, B. subtilis, Escherichia coli, and Pseudomonas aeruginosa, were examined for the ability to remove Ag+, Cd2+, Cu2+, and La3+ from solution by batch equilibration methods. Cd and Cu sorption over the concentration range 0.001 to 1 mM was described by Freundlich isotherms. At 1 mM concent...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.55.12.3143-3149.1989
更新日期:1989-12-01 00:00:00
abstract::Wolbachia, a common bacterial endosymbiont of insects, has been shown to protect its hosts against a wide range of pathogens. However, not all strains exert a protective effect on their host. Here we assess the effects of two divergent Wolbachia strains, wAlbB from Aedes albopictus and wMelPop from Drosophila melanoga...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.06751-11
更新日期:2012-03-01 00:00:00
abstract::In Pseudomonas aeruginosa, the catabolite repression control (Crc) protein repressed the formation of the blue pigment pyocyanin in response to a preferred carbon source (succinate) by interacting with phzM mRNA, which encodes a key enzyme in pyocyanin biosynthesis. Crc bound to an extended imperfect recognition seque...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00026-12
更新日期:2012-07-01 00:00:00
abstract::"Candidatus Nitrosotenuis uzonensis" is the only cultured moderately thermophilic member of the thaumarchaeotal order Nitrosopumilales (NP) that contains many mesophilic marine strains. We examined its membrane lipid composition at different growth temperatures (37°C, 46°C, and 50°C). Its lipids were all membrane-span...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.01332-19
更新日期:2019-10-01 00:00:00
abstract::The temperate bacteriophage phiLC3, isolated from Lactococcus lactis subsp. cremoris, has an isometric head and a flexible tail containing 1 major protein and 8 minor proteins. Infection of a permissive L. lactis host strain yields a burst of about 50 phages per infected cell with a latent period of 60 min. A detailed...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.57.11.3206-3211.1991
更新日期:1991-11-01 00:00:00
abstract::Perchlorate is a known health hazard for humans, fish, and other species. Therefore, it is important to assess the response of an ecosystem exposed to perchlorate contamination. The data reported here show that a liquid chromatography-mass spectrometry-based proteomics approach for the detection of perchlorate-reducin...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.01323-10
更新日期:2011-02-01 00:00:00
abstract::Staphylococcus aureus is a gram-positive pathogen that causes a variety of diseases, including bovine mastitis, which has severe economic consequences. Standard antibiotic treatment results in selection of resistant strains, leading to a need for alternative treatments, such as bacteriophage therapy. Forty-nine S. aur...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02641-08
更新日期:2009-07-01 00:00:00
abstract::We developed a biphasic culture system consisting of 4 ml of brucella agar (BA) and 6 ml of brucella broth (BB) in 25-cm2 tissue culture flasks, which were incubated in air (BB/BAa) or in a gas mixture of 5% O2, 10% CO2, and 85% N2 (BB/BAg). These media were also used with a supplement consisting of ferrous sulfate, s...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.45.1.284-289.1983
更新日期:1983-01-01 00:00:00
abstract::Noroviruses (NoV) in 78 wastewater samples from Luxembourg were quantified, cloned, and sequenced in 2008-2009. The concentrations of NoV genogroup II and the relative occurrences of certain genotypes changed significantly during the winter season. NoV genogroup I was frequently detected by real-time reverse transcrip...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00632-11
更新日期:2011-08-01 00:00:00
abstract::Biogenic amines may reach concentrations of public health concern in some cheeses. To minimize biogenic amine buildup in raw milk cheese, high-pressure treatments of 400 or 600 MPa for 5 min were applied on days 21 and 35 of ripening. On day 60, counts of lactic acid bacteria, enterococci, and lactobacilli were 1 to 2...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.03368-12
更新日期:2013-02-01 00:00:00
abstract::Eubacterium lentum is a gram-positive, nonsporeforming, nonmotile, asaccharolytic anaerobe. In the present investigations, 3 E. lentum strains (group E) isolated from rat feces were compared with 30 E. lentum strains (groups A, B, C, and D) previously studied by Macdonald et al. (I. A. Macdonald, J. F. Jellet, D. E. M...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.47.1.39-43.1984
更新日期:1984-01-01 00:00:00
abstract::Despite the importance of human noroviruses (NoVs) in public health, little information concerning the effectiveness of ozone against NoVs is available. We determined the efficacy of ozone disinfection using murine norovirus (MNV) as a surrogate of human NoV. MNV in ozone demand-free buffer was exposed to a predetermi...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.01955-09
更新日期:2010-02-01 00:00:00
abstract::Fermentation strategies for the production of poly(3-hydroxybutyrate) (PHB) from whey by recombinant Escherichia coli strain CGSC 4401 harboring the Alcaligenes latus polyhydroxyalkanoate (PHA) biosynthesis genes were developed. The pH-stat fed-batch cultures of E. coli CGSC 4401 harboring pJC4, a stable plasmid conta...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.66.8.3624-3627.2000
更新日期:2000-08-01 00:00:00
abstract::The rhizobial bacterium Bradyrhizobium japonicum functions as a nitrogen-fixing symbiont of the soybean plant (Glycine max). Plants are capable of producing an oxidative burst, a rapid proliferation of reactive oxygen species (ROS), as a defense mechanism against pathogenic and symbiotic bacteria. Therefore, B. japoni...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00047-11
更新日期:2011-06-01 00:00:00
abstract::A glycosyltransferase, involved in the synthesis of cyclic maltosylmaltose [CMM; cyclo-{-->6)-alpha-D-Glcp(1-->4)-alpha-D-Glcp(1-->6)-alpha-D-Glcp(1-->4)-alpha-D-Glcp(1-->}] from starch, was purified to homogeneity from the culture supernatant of Arthrobacter globiformis M6. The CMM-forming enzyme had a molecular mass...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.72.2.1065-1071.2006
更新日期:2006-02-01 00:00:00
abstract::The addition of positively charged colloidal materials to the growth medium markedly increased the concentration of cellulase enzymes produced by Trichoderma reesei Rut-C30. Filter paper activities of up to 4 and 13 IU/ml have been achieved by the addition of colloidal materials, using 3% lactose and 3% cellulose, res...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.49.4.934-938.1985
更新日期:1985-04-01 00:00:00
abstract::Respiratory denitrification is not always adequately established when bacteria are characterized. We have tested a simple method that allows one to evaluate whether the two necessary criteria to claim denitrification have been met, namely, that N(inf2) or N(inf2)O is produced from nitrate or nitrite and that this redu...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.61.3.1110-1115.1995
更新日期:1995-03-01 00:00:00
abstract::Understanding of functional diversity of microbial populations has lagged description of their molecular diversity. Differences in substrate specificity, kinetics, products, and regulation can dramatically influence phenotypic variation among closely related strains, features that are missed when the strains studied a...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.01905-13
更新日期:2013-11-01 00:00:00
abstract::The Alvord Basin in southeast Oregon contains a variety of hydrothermal features which have never been microbiologically characterized. A sampling of Murky Pot (61 degrees C; pH 7.1) led to the isolation of a novel arsenic-metabolizing organism (YeAs) which produces an arsenic sulfide mineral known as beta-realgar, a ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00371-07
更新日期:2007-09-01 00:00:00
abstract::Staphylococcal enterotoxins (SE) can cause toxin-mediated disease, and those that function as superantigens are implicated in the pathogenesis of allergic diseases. The prevalence of 19 enterotoxin genes was determined by PCR in clinical S. aureus strains derived from wounds (108) and blood (99). We performed spa typi...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00272-09
更新日期:2009-11-01 00:00:00
abstract::When mixed ruminal bacteria were incubated with a pancreatic casein hydrolysate and free amino acids of a similar composition, rates of ammonia production were much greater for peptides than for amino acids. The pancreatic digest of casein was then fractionated with 90% isopropyl alcohol. Hydrophobic peptides which di...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.53.9.2021-2025.1987
更新日期:1987-09-01 00:00:00