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111.
Mustafa Sari 《Environmental Biology of Fishes》2008,81(1):21-23
A member of the Cyprinidae family, the Chalcalburnus tarichi is a fish species that only inhabits the Lake Van Basin. The Lake Van represents an interesting ecosystem in the world, known
as the biggest soda lake in the world, in that its water is highly alkaline with a pH of 9.8. C. tarichi has bright-silver color, its back is grayish green, and the abdominal region is silver. Its body is covered with small scales,
and its eyes are large. It feeds on phyto and zooplanktons. Its average life span is 7 years, and the fish reaches reproductive
maturity at 3 years old. C. tarichi is an diadrom fish that lives in the lake, but during the reproduction period it immigrates to the surrounding freshwater
rivers returning after the reproduction period of April–July. In the past, pearl mullet was an attractive fresh fish for the
local people and was easily caught during the spawning migration, resulting in over-fishing. The species was one of the highly
endangered animals of Turkey before conservation studies, some 10 years ago, have started. At present, illegal fishing activities
declined, although some locals are continuing to fish during the spawning season. 相似文献
112.
Skeletal growth and tissue remodelling processes are characterized by an elevated collagen and proteoglycan biosynthesis.
The xylosyltransferases I and II are the rate-limiting step enzymes in proteoglycan biosynthesis and serum xylosyltransferase
(XT) activity has been shown to be a biomarker for the actual proteoglycan biosynthesis rate. Here, XT, alkaline phosphatase
(ALP), bone ALP (BALP) activities were measured in 133 juvenile Caucasians. Serum XT activities in juveniles were elevated
and significantly correlated with ALP and BALP. In an osteoblast-like cell model using SAOS-2 cells mineralization and bone
nodule formation were induced and XT-I, XT-II and ALP were monitored. Induction of mineralization in SAOS-2 cells resulted
in a long-term increase of XT-I mRNA and enzyme activity, which could be paralleled with elevated ALP activity. In addition,
HGH and IGF-I treatment of SAOS-2 cells led to an increased expression of XT-I and ALP. These results point to skeletal growth
and tissue remodeling as a cause of the high XT activity in children. 相似文献
113.
Production,characterization and gene cloning of the extracellular enzymes from the marine-derived yeasts and their potential applications 总被引:1,自引:0,他引:1
In this review article, the extracellular enzymes production, their properties and cloning of the genes encoding the enzymes from marine yeasts are overviewed. Several yeast strains which could produce different kinds of extracellular enzymes were selected from the culture collection of marine yeasts available in this laboratory. The strains selected belong to different genera such as Yarrowia, Aureobasidium, Pichia, Metschnikowia and Cryptococcus. The extracellular enzymes include cellulase, alkaline protease, aspartic protease, amylase, inulinase, lipase and phytase, as well as killer toxin. The conditions and media for the enzyme production by the marine yeasts have been optimized and the enzymes have been purified and characterized. Some genes encoding the extracellular enzymes from the marine yeast strains have been cloned, sequenced and expressed. It was found that some properties of the enzymes from the marine yeasts are unique compared to those of the homologous enzymes from terrestrial yeasts and the genes encoding the enzymes in marine yeasts are different from those in terrestrial yeasts. Therefore, it is of very importance to further study the enzymes and their genes from the marine yeasts. This is the first review on the extracellular enzymes and their genes from the marine yeasts. 相似文献
114.
A mixed culture containing two recombinant Bacillus subtilis strains; was used to hydrolyze 1% chicken feather; both were previously transformed with late-expressed and early expressed
alkaline protease (aprE) carrying plasmids pS1 and p5.2, respectively. Proteolytic and keratinolytic activities of the mixed culture increased in
parallel with those of the culture of B. subtilis DB100 (p5.2), and both were higher than that of B. subtilis (pS1) cultures. On the other hand, data indicated that degradation of feather by the recombinant strains B. subtilis DB100 (p5.2), was greatly enhanced when using a previously optimized medium. High levels of free amino groups as well as
soluble proteins were also obtained. The concentration of amino acids was considerably increased during the fermentation process.
It was found that, the amino acids Phe, Gly and Tyr were the major amino acids liberated in the cultures initiated by both
strains. Results render these recombinant strains suitable for application in feather biodegradation large scale processes. 相似文献
115.
A salt-tolerant alkaliphilic actinomycete, Mit-1 was isolated from Mithapur, coastal region of Gujarat, India. The strain
was identified as Streptomyces clavuligerus and based on 16S rRNA gene sequence (EU146061) homology; it was related to Streptomyces sp. (AY641538.1). The organism could grow with up to 15% salt and pH 11, optimally at 5% and pH 9. It was able to tolerate
and secrete alkaline protease in the presence of a number of organic solvents including xylene, ethanol, acetone, butanol,
benzene and chloroform. Besides, it could also utilize these solvents as the sole source of carbon with significant enzyme
production. However, the organism produced spongy cell mass with all solvents and an orange brown soluble pigment was evident
with benzene and xylene. Further, the enzyme secretion increased by 50-fold in the presence of butanol. With acetone and ethanol;
the enzyme was highly active at 60–80°C and displayed optimum activity at 70°C. The protease was significantly stable and
catalyzed the reaction in the presence of xylene, acetone and butanol. However, ethanol and benzene affected the catalysis
of the enzyme adversely. Crude enzyme preparation was more stable at 37°C in solvents as compared to partially purified and
purified enzymes. The study holds significance as only few salt-tolerant alkaliphilic actinomycetes are explored and information
on their enzymatic potential is still scares. To the best of our knowledge this is the first report on organic solvent tolerant
protease from salt-tolerant alkaliphilic actinomycetes. 相似文献
116.
Shereen Sabet Lamine Diallo Lauren Hays Woosung Jung Jesse G. Dillon 《Extremophiles : life under extreme conditions》2009,13(4):643-656
Solar salterns are extreme hypersaline environments that are five to ten times saltier than seawater (150–300 g L−1 salt concentration) and typically contain high numbers of halophiles adapted to tolerate such extreme hypersalinity. Thirty-five
halophile cultures of both Bacteria and Archaea were isolated from the Exportadora de Sal saltworks in Guerrero Negro, Baja
California, Mexico. 16S rRNA sequence analysis showed that these cultured isolates included members belonging to the Halorubrum, Haloarcula, Halomonas, Halovibrio, Salicola, and Salinibacter genera and what may represent a new archaeal genus. For the first time, metabolic substrate usage of halophile isolates was
evaluated using the non-colorimetric BIOLOG Phenotype MicroArray™ plates. Unique carbon substrate usage profiles were observed,
even for closely related Halorubrum species, with bacterial isolates using more substrates than archaeal cultures. Characterization of these isolates also included
morphology and pigmentation analyses, as well as salinity tolerance over a range of 50–300 g L−1 salt concentration. Salinity optima varied between 50 and 250 g L−1 and doubling times varied between 1 and 12 h.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
117.
Subramani Ramesh Mahalingam Rajesh Narayanasamy Mathivanan 《Bioprocess and biosystems engineering》2009,32(6):791-800
Totally 191 different marine actinomycetes were isolated from 256 different marine samples collected from the Bay of Bengal
and its associated Pulicat lake and Pichavaram mangrove, India. Among them, 157 produced caseinase, 113 produced gelatinase
and 108 produced both the protease enzymes. An isolate coded as MML1614 was selected for further study as it exhibited high
proteolytic activity. The MML1614 was identified as Streptomyces fungicidicus based on polyphasic taxonomical approach including 16S rRNA sequence analysis. The culture conditions were standardized for
the growth and protease production in S. fungicidicus MML1614. The protease was isolated from a 6-day-old culture filtrate of S. fungicidicus MML1614 and partially purified up to 4.5-fold. The protease was optimally active at pH 9 and 40 °C and it was stable up to
pH 11 and 60 °C. PMSF and NaCl inhibited the enzyme activity up to 22 and 11%, respectively. The partially purified protease
removed the blood stain more effectively when combined with different detergents than the detergents alone. 相似文献
118.
Janka Kubálková Vladimíra Tomečková Pál Perjési Juraj Guzy 《Central European Journal of Biology》2009,4(1):90-96
The cytotoxic and protective effects of selected synthetic chalcone analogues have been shown in previous studies. We studied
their cytotoxic effect on the modification of mitochondrial membrane potential and on DNA. The first spectral information
about the methoxy group as well as the dimethylamino substituent in E-2-arylmethylene-1-benzosuberones molecule was obtained
by absorption and emission spectra. The cytotoxic effect of both cyclic chalcone analogues on DNA were detected by alkaline
single-cell gel electrophoresis. Better fluorescent chalcone analogue E-2-(4′-dimethylamino-benzylidene)-1-benzosuberone was
studied further in fresh isolated mitochondria. The decrease of rat liver mitochondria membrane potential (Δψ) was observed
by fluorescence emission spectra. For the collapsing of mitochondrial potentials and as the negative control of mitochondrial
function the CCCP uncoupler was used. The absorption maximum of the methoxy group was found at a shorter wavelength (λ = 335
nm) than that of the dimethylamino group (λ = 406 nm). The excitation spectra were very similar to the absorption spectra
for both molecules but the emission spectra showed a better fluorescence for dimethylamino derivative. After the addition
of E-2-(4′-dimethylamino-benzylidene)-1-benzosuberone to the intact mitochondria the decrease of mitochondrial membrane potential
Δψ was observed by emisssion fluorescence spectra. Both cyclic chalcone analogues induced DNA damage, which was detected by
alkaline comet assay. Mainly the apoptotic cells were detected, but necrotic cells were also present. Similarities in the
percentages of DNA migration from the head were observed in both treatment groups. Both benzosuberones, with dimethylamino-
and methoxy- substituent, were very active biologically, as shown by DNA results of the comet assay. Due to its better fluorescence
properties, only the fluorophore with dimethylamino substituent was selected for further study of the function of rat liver
mitochondria. Decline of mitochondrial function as well as mitochondrial DNA damage were evident between experimental and
control groups. 相似文献
119.
Maya Nustorova Diana Braikova Adriana Gousterova Evgenia Vasileva-Tonkova Peter Nedkov 《World journal of microbiology & biotechnology》2006,22(4):383-390
Summary The effect of adding alkaline hydrolysate of sheep’s wool waste on the chemical and microbiological properties of a park soil
(Sofia, Bulgaria) has been assessed in a 9 month laboratory experiment. The waste product contained 75–80% water-soluble materials:
peptides, amino acids, salts, dyes, lipids, some carbohydrates, potassium ions, and it seemed likely that the hydrolysate
obtained could be used as a harmless and valuable fertilizer in agriculture. It was demonstrated that the organic material
positively influenced microbial soil populations and ryegrass growth. As the remaining partially degraded keratin is highly
dispersed it should act as a slow release fertilizer thus feeding plants additionally. The results suggest that the wool hydrolysate
is beneficial for improving soil characteristics and could successfully be used as alternative biofertilizer. The authors
hope that by utilization of the keratin wastes, the environment around leather and fur plants could be influenced positively
and that the expense of removing the wastes to controlled landfill sites and part of the expenses for sustaining the latter
will be saved. 相似文献
120.
Javier Arias 《Inorganica chimica acta》2011,365(1):501-504
The crown ether isocyanide CNR (R = benzo-15-crown-5) reacts with silver(I) salts in the appropriate molar ratio to give [Ag(CNR)n]X (n = 1, 2; X = CF3SO3, BF4). X-ray diffraction studies of [Ag(CF3SO3)(CNR)] show the molecules associated in a dinuclear manner with an antiparallel orientation. The silver centers are tetracoordinated to the isocyanide and to three oxygens, one from the triflate anion and two from the second crown ether in the dimer. The molecular structure displays five cycles: the two 15-crown ether rings, two five-membered argentacycles and a 22-membered diargentacycle. The crown ether in these complexes is able to detect alkaline cations from M(CF3SO3) (M = Li, Na, K) by NMR in d6-acetone solutions, and to distinguish Li+-Na+ from K+. 相似文献