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1.
The effects of temperature and light on the growth and geosmin production of Lyngbya kuetzingii were determined. Of the three temperatures tested, 10, 25 and 35°C, the maximal geosmin concentration and geosmin productivity
were yielded at 10°C, while the highest chl a production was observed at 25°C. In the studies on light intensity, the maximal geosmin concentration and geosmin productivity
were observed at 10 μmol m−2 s−1, while the highest chl a production was at 20 μmol m−2 s−1. It was suggested that more geosmin was synthesized with lower chl a demand. Meanwhile, the relative amounts of extra- and intracellular geosmin were investigated. Under optimum growth conditions
(20 μmol m−2 s−1, 25°C; BG-11 medium), the amounts of extracellular geosmin increased as the growth progressed and reached the maximum in
the stationary phase, while the intracellular geosmin reached its maximum value in the late exponential phase, and then began
to decline. However, under the low temperature (10°C) or light (10 μmol m−2 s−1) conditions, more intracellular geosmin was synthesized and mainly accumulated in the cells. The proportions of extracellular
geosmin were high, to 33.33 and 32.27%, respectively, during the stationary phase at 35°C and 20 μmol m−2 s−1. It was indicated that low temperature or light could stimulate geosmin production and favor the accumulation of geosmin
in cells, while more intracellular geosmin may be released into the medium at higher temperatures or optimum light intensity. 相似文献
2.
Bacterioplankton abundance and production, chlorophyll a (Chl a) concentrations and primary production (PP) were measured from the equatorial Indian Ocean (EIO) during northeast (NEM),
southwest (SWM) and spring intermonsoon (SpIM) seasons from 1°N to 5°S along 83°E. The average bacterial abundance was 0.52 ± 0.29,
0.62 ± 0.33 and 0.46 ± 0.19 (× 108 cells l−1), respectively during NEM, SWM and SpIM in the top 100 m. In the deep waters (200 m and below), the bacterial counts averaged
∼0.35 ± 0.14 × 108 cells l−1 in SWM and 0.39 ± 0.16 × 108 cells l−1 in SpIM. The 0–120 m column integrated bacterial production (BP) ranged from 19 to 115 and from 10 to 51 mg C m−2 d−1 during NEM and SWM, respectively. Compared with many open ocean locations, bacterial abundance and production in this region
are lower. The bacterial carbon production, however, is notably higher than that of phytoplankton PP (BP:PP ratio 102% in
SWM and 188% in NEM). With perpetually low PP (NEM: 20, SWM: 18 and SpIM: 12 mg C m−2 d−1) and Chl a concentration (NEM: 16.5, SWM: 15.0 and SpIM: 20.9 mg m−2), the observed bacterial abundance and production are pivotal in the trophodynamics of the EIO. Efficient assimilation and
mineralization of available organics by bacteria in the euphotic zone might serve a dual role in the ultra-oligotrophic regions
including EIO. Thus, bacteria probably sustain microheterotrophs (micro- and meso-zooplankton) through microbial loop. Further,
rapid mineralization by bacteria will make essential nutrients available to autotrophs. 相似文献
3.
Lamia Trabelsi Hatem Ben Ouada Hassen Bacha Mohamed Ghoul 《Journal of applied phycology》2009,21(4):405-412
The effects of light intensity and temperature on Arthrospira platensis growth and production of extracellular polymeric substances (EPS) in batch culture were evaluated using a three-level, full-factorial
design and response surface methodology. Three levels were tested for each parameter (temperature: 30, 35, 40°C; light intensity:
50, 115, 180 μmol photons m−2 s−1). Both growth and EPS production are influenced mainly by the temperature factor but the interaction term temperature*light
intensity also had a significant effect. In addition, conditions optimising EPS production are different from those optimising
growth. The highest growth rate (0.414 ± 0.003 day−1) was found at the lowest temperature (30°C) and highest light intensity (180 μmol photons m−2 s−1) tested, no optima were detectable within the given test range. Obviously, optima for growth must be at a temperature lower
than 30°C and a light intensity higher than 180 μmol photons m−2 s−1. For EPS production, light intensity had a positive linear effect (optimum obviously higher than 180 μmol photons m−2 s−1), but for the temperature parameter a maximum effect was detectable at 35°C. 相似文献
4.
Cui Fengjie Li Yin Liu Zhiqiang Zhao Hui Ping Lifeng Ping Liying Yang Yinan Xue Yaping Yan Lijiao 《World journal of microbiology & biotechnology》2009,25(4):721-725
The objective of this study was to maximize production of xylanase by a newly isolated strain Penicillium thiersii ZH-19. Response surface methodology was employed to study the effects of significant factors such as pH, temperature, xylan
concentration, and cultivation time, on the production of xylanase by Penicillium thiersii ZH-19. The optimal fermentation parameters for enhanced xylanase production were found to be pH 7.72, temperature 24.8°C, xylan
13.2 g l−1 and the fermentation time 125.8 h. The model predicted a xylanase activity of 75.24 U ml−1. Verification of the optimization showed that the maximum xylanase production reached 73.50 U mL−1 in the flask experiments and 80.23 U mL−1 in the scale of 15-L fermenter under the optimal condition. 相似文献
5.
Huiying Luo Jiang Li Jun Yang Hui Wang Yuhui Yang Huoqing Huang Pengjun Shi Tiezheng Yuan Yunliu Fan Bin Yao 《Extremophiles : life under extreme conditions》2009,13(5):849-857
A complete gene, xyl10C, encoding a thermophilic endo-1,4-β-xylanase (XYL10C), was cloned from the acidophilic fungus Bispora sp. MEY-1 and expressed in Pichia pastoris. XYL10C shares highest nucleotide and amino acid sequence identities of 57.3 and 49.7%, respectively, with a putative xylanase
from Aspergillus fumigatus Af293 of glycoside hydrolase family 10. A high expression level in P. pastoris (73,400 U ml−1) was achieved in a 3.7–l fermenter. The purified recombinant XYL10C was thermophilic, exhibiting maximum activity at 85°C,
which is higher than that reported from any fungal xylanase. The enzyme was also highly thermostable, exhibiting ~100% of
the initial activity after incubation at 80°C for 60 min and >87% of activity at 90°C for 10 min. The half lives of XYL10C
at 80 and 85°C were approximately 45 and 3 h, respectively. It had two activity peaks at pH 3.0 and 4.5–5.0 (maximum), respectively,
and was very acid stable, retaining more than 80% activity after incubation at pH 1.5−6.0 for 1 h. The enzyme was resistant
to Co2+, Mn2+, Cr3+ and Ag+. The specific activity of XYL10C for oat spelt xylan was 18,831 U mg−1. It also had wide substrate specificity and produced simple products (65.1% xylose, 25.0% xylobiose and 9.9% xylan polymer)
from oat spelt xylan. 相似文献
6.
Terence J. Evens Randall P. Niedz Gary J. Kirkpatrick 《Journal of applied phycology》2008,20(4):411-422
The microalga Haematococcus pluvialis Flotow has been the subject of a number of studies concerned with maximizing astaxanthin production for use in animal feeds
and for human consumption. Several of these studies have specifically attempted to ascertain the optimal temperature and irradiance
combination for growth of H. pluvialis, but there has been a great deal of disagreement between laboratories. “Ideal” levels of temperature and irradiance have
been reported to range from 14 to 28°C and 30 to 200 μmol photons m−2 s−1. The objective of the present study was to simultaneously explore temperature and irradiance effects for a single strain
of H. pluvialis (UTEX 2505) across an experimental region that encompassed the reported “optimal” combinations of these factors for multiple
strains. To this end, a two-dimensional experimental design based on response surface methodology (RSM) was created. Maximum
growth rates for UTEX 2505 were achieved at 27°C and 260 μmol photons m−2 s−1, while maximum quantum yield for stable charge separation at PSII (Fv/Fm) was achieved at 27°C and 80 μmol photons m−2 s−1. Maximum pigment concentrations correlated closely with maximum Fv/Fm. Numeric optimization of growth rate and Fv/Fm produced an optimal combination of 27°C and 250 μmol photons m−2 s−1. Polynomial models of the various response surfaces were validated with multiple points and were found to be very useful
for predicting several H. pluvialis UTEX 2505 responses across the entire two-dimensional experimental design space. 相似文献
7.
8.
Two 60-day experiments were conducted to study the influence of photon flux density (PFD) and temperature on the attachment
and development of Gloiopeltis tenax and Gloiopeltis furcata tetraspores. In the first experiment, tetraspores of the two Gloiopeltis species were incubated at five temperature ranges (8°C, 12°C, 16°C, 20°C, 24°C) under a constant PFD of 80 μmol photons m−2 s−1 with a photoperiod of 12:12. In a second experiment, tetraspores were incubated under five PFD gradients (30, 55, 80, 105,
130 μmol photons m−2 s−1) at a constant temperature of 16°C with a photoperiod of 12:12. Maximum density of attached tetraspores was observed at 16°C
for both species. Maximum per cent of spore germinating into disc was recorded at 12–16°C for G. tenax and 8–12°C for G. furcata. Maximum per cent of discs producing erect axes for G. tenax and G. furcata were recorded at 24°C and 20°C, respectively. Light had no significant effect on tetraspore attachment and developing into
disc, but it affected the growth, sprouting and survival of its discs. Under 30–55 μmol photons m−2 s−1, the discs of the two species of Gloiopeltis did not form thallus until the end of the experiment. Optimum PFD range for G. tenax discs was 80–105 μmol photons m−2 s−1, whilst it was 80–130 μmol photons m−2 s−1 for G. furcata. Results presented in this study are expected to assist the progress of artificial seeding of Gloiopeltis. 相似文献
9.
G. Selvakumar S. Kundu Piyush Joshi Sehar Nazim A. D. Gupta P. K. Mishra H. S. Gupta 《World journal of microbiology & biotechnology》2008,24(7):955-960
Pantoea dispersa strain 1A is a Gram-negative rod-shaped, yellow-pigmented bacterium isolated on nutrient agar plates incubated at 4°C. The
identity of the bacterium was confirmed by sequencing of the 16 S rRNA gene. It was capable of growing at temperatures ranging
from 4 to 42°C, but maximum growth was observed at 30°C. It is endowed with multiple plant growth promotion attributes such
as phosphate solubilization, IAA production, siderophore production and HCN production, which are expressed differentially
at sub-optimal temperatures (15 and 4°C). It was able to solubilize phosphate (17.6 μg of P2O5 ml−1 day−1), and produce IAA (3.7 μg ml−1 day−1), at 15°C. Qualitative detection of siderophore production and HCN were also observed at 15°C. At 4°C it was found to express
all the plant growth promotion attributes. This bacterial isolate was able to positively influence and promote the growth
and nutrient uptake parameters of wheat (cv. VL.802) under glasshouse conditions. Hence in the context, of cold wheat-growing
environments, it is proposed that Pantoea dispersa 1A (MTCC 8706), could be deployed as an inoculant to attain the desired results of bacterization. 相似文献
10.
M. Bustamante M. E. González A. Cartes M. C. Diez 《Journal of industrial microbiology & biotechnology》2011,38(1):189-197
The present work optimized the initial pH of the medium and the incubation temperature for ligninolytic enzymes produced by
the white-rot fungus Anthracophyllum discolor. Additionally, the effect of soya lecithin on mycelial growth and the production of ligninolytic enzymes in static batch
cultures were evaluated. The critical micelle concentration of soya lecithin was also studied by conductivity. The effects
of the initial pH (3, 4, and 5) and incubation temperature (20, 25, and 30°C) on different enzymatic activities revealed that
the optimum conditions to maximize ligninolytic activity were 26°C and pH 5.5 for laccase and manganese peroxidase (MnP) and
30°C and pH 5.5 for manganese-independent peroxidase (MiP). Under these culture conditions, the maximum enzyme production
was 10.16, 484.46, and 112.50 U L−1 for laccase, MnP, and manganese-independent peroxidase MiP, respectively. During the study of the effect of soya lecithin
on A. discolor, we found that the increase in soya lecithin concentration from 0 to 10 g L−1 caused an increase in mycelial growth. On the other hand, in the presence of soya lecithin, A. discolor produced mainly MnP, which reached a maximum concentration of 30.64 ± 4.61 U L−1 after 25 days of incubation with 1 g L−1 of the surfactant. The other enzymes were produced but to a lesser extent. The enzymatic activity of A. discolor was decreased when Tween 80 was used as a surfactant. The critical micelle concentration of soya lecithin calculated in our
study was 0.61 g L−1. 相似文献
11.
The distribution of picoplankton and nanoplankton in Kongsfjorden,Svalbard during late summer 2006 总被引:2,自引:0,他引:2
Abundance and biomass of pico- (<2 μm) and nanoplankton (2–20 μm) were investigated in relation to hydrography in Kongsfjorden,
Svalbard (79°N, 12°E) during late summer 2006. Autotrophic and heterotrophic picoplankton abundance ranged from 0.1 × 106 to 35.2 × 106 cells L−1 and from 0.4 × 106 to 20.3 × 106 cells L−1, respectively. The highest number of bacteria in the entire water column was recorded at station 2 at 10 m (22.3 × 108 cells L−1); the lowest concentration was observed at station 1 (6.0 × 108 cells L−1). The abundance of autotrophic and heterotrophic nanoplankton varied from 0.4 × 105 cells L−1 to 46 × 105 cells L−1 and from 0.3 × 106 to 9.1 × 106 cells L−1, respectively. Our results demonstrated that heterotrophic nanoflagellates and bacteria in Kongsfjorden microbial community
were relatively important. The structure of plankton communities integrated with environmental variables could act as indicators
of the variability of the inflow of Atlantic Water into Kongsfjorden. 相似文献
12.
Ha-Young Park Hye-Jung Kim Jung-Kul Lee Doman Kim Deok-Kun Oh 《World journal of microbiology & biotechnology》2008,24(8):1553-1558
A recombinant β-galactosidase from Sulfolobus solfataricus produced galactooligosaccharides (GOS) from lactose by transgalactosylation. The enzyme activity for GOS production was maximal
at pH 6.0 and 85°C. The half-lives of the recombinant β-galactosidase at 70, 75, 80, 85, and 90°C were 700, 111, 72, 43, and
2.4 h, respectively, and its deactivation energy was 213 kJ mol−1. The optimal amount of enzyme for effective GOS production was 3.6 U of enzyme ml−1. GOS production increased with increasing lactose concentration, whereas the yield of GOS from lactose was almost constant.
The rates of hydrolysis and transgalactosylation reactions increased with increasing temperature but the final concentration
of GOS was maximal at 80°C. Under the conditions of pH 6.0, 80°C, 600 g lactose l−1, and 3.6 U enzyme ml−1, 315 g GOS l−1 were obtained for 56 h with a yield of 52.5% (w/w). The β-galactosidase from S. solfataricus produced GOS with the highest concentration and yield among thermostable β-galactosidases reported to date. 相似文献
13.
In winter of 2009/2010, Aphanizomenon flos-aquae bloomed in the ice and snow covered oligo-mesotrophic Lake Stechlin, Germany. The photosynthesis of the natural population was measured at eight temperatures in the range of 2–35°C, at nine different irradiance levels in the range of 0–1,320 μmol m−2 s−1 PAR at each applied temperature. The photoadaptation parameter (I k) and the maximum photosynthetic rate (P max) correlated positively with the temperature between 2 and 30°C, and there was a remarkable drop in both parameters at 35°C. The low I k at low temperatures enabled the active photosynthesis of overwintering populations at low irradiance levels under ice and snow cover. The optimum of the photosynthesis was above 20°C at irradiances above 150 μmol m−2 s−1. At lower irradiance levels (7.5–30 μmol m−2 s−1), the photosynthesis was the most intensive in the temperature range of 2–5°C. The interaction between light and temperature allowed the proliferation of A. flos-aquae in Lake Stechlin resulting in winter water bloom in this oligo-mesotrophic lake. The applied 2°C is the lowest experimental temperature ever in the photosynthesis/growth studies of A. flos-aquae, and the results of the P–I and P–T measurements provide novel information about the tolerance and physiological plasticity of this species. 相似文献
14.
Anjali Madhavan Sriappareddy Tamalampudi Aradhana Srivastava Hideki Fukuda Virendra S. Bisaria Akihiko Kondo 《Applied microbiology and biotechnology》2009,82(6):1037-1047
Previously, a Saccharomyces cerevisiae strain was engineered for xylose assimilation by the constitutive overexpression of the Orpinomyces xylose isomerase, the S. cerevisiae xylulokinase, and the Pichia stipitis SUT1 sugar transporter genes. The recombinant strain exhibited growth on xylose, under aerobic conditions, with a specific growth
rate of 0.025 h−1, while ethanol production from xylose was achieved anaerobically. In the present study, the developed recombinant yeast was
adapted for enhanced growth on xylose by serial transfer in xylose-containing minimal medium under aerobic conditions. After
repeated batch cultivations, a strain was isolated which grew with a specific growth rate of 0.133 h−1. The adapted strain could ferment 20 g l−1 of xylose to ethanol with a yield of 0.37 g g−1 and production rate of 0.026 g l−1 h−1. Raising the fermentation temperature from 30°C to 35°C resulted in a substantial increase in the ethanol yield (0.43 g g−1) and production rate (0.07 g l−1 h−1) as well as a significant reduction in the xylitol yield. By the addition of a sugar complexing agent, such as sodium tetraborate,
significant improvement in ethanol production and reduction in xylitol accumulation was achieved. Furthermore, ethanol production
from xylose and a mixture of glucose and xylose was also demonstrated in complex medium containing yeast extract, peptone,
and borate with a considerably high yield of 0.48 g g−1. 相似文献
15.
Laura Pinilla Rodrigo Torres Claudia Ortiz 《World journal of microbiology & biotechnology》2011,27(11):2521-2528
Two wild strains of Zymomonas mobilis were isolated (named as ML1 and ML2) from sugar cane molasses obtained from different farms of Santander, Colombia. Initially,
selection of the best ethanol-producer strains was carried out using ethanol production parameters obtained with a commercial
strain Z. mobilis DSM 3580. Three isolated strains were cultivated in a culture medium containing yeast extract, peptone, glucose and salts,
at pH 6 and 32°C with stirring rate of 65 rpm during 62 h. The best results of ethanol production were obtained with the native
strain ML1, reaching a maximum ethanol concentration of 79.78 g l−1. ML1 and ML2 strains were identified as Z.
mobilis, according to the morphology, biochemical tests and molecular characterization by PCR of specific DNA sequences from Z. mobilis. Subsequently, the effect of different nitrogen sources on production of ethanol was evaluated. The best results were obtained
using urea at a 0.73 g/l. In this case, maximum concentration of ethanol was 83.81 g l−1, with kinetic parameters of yield of ethanol on biomass (YP/X) = 69.01(g g−1), maximum volumetric productivity of ethanol (Qpmax) = 2.28 (g l−1 h−1), specific productivity of ethanol (qP) = 3.54 (h−1) and specific growth rate (μ) = 0.12 h−1. Finally, we studied the effect of different culture conditions (pH, temperature, stirring, C/N ratio) with a Placket-Burman′s
experimental design. This optimization indicated that the most significant variables were temperature and stirring. In the
best culture conditions a significant increase in all variables of response was achieved, reaching a maximum ethanol concentration
of 93.55 g l−1. 相似文献
16.
Bustard MT McEvoy EM Goodwin JA Burgess JG Wright PC 《Applied microbiology and biotechnology》2000,54(3):424-431
The aerobic biodegradation of high concentrations of 1-propanol and 2-propanol (IPA) by a mixed microbial consortium was
investigated. Solvent concentrations were one order of magnitude greater than any previously reported in the literature. The
consortium utilized these solvents as their sole carbon source to a maximum cell density of 2.4 × 109 cells ml−1. Enrichment experiments with propanol or IPA as carbon sources were carried out in batch culture and maximum specific growth
rates (μmax) calculated. At 20 °C, μ
max values were calculated to be 0.0305 h−1 and 0.1093 h−1 on 1% (v/v) IPA and 1-propanol, respectively. Growth on propanol and IPA was carried out between temperatures of 10 °C and
45 °C. Temperature shock responses by the microbial consortium at temperatures above 45 °C were demonstrated by considerable
cell flocculation. An increase in propanol substrate concentration from 1% (v/v) to 2% (v/v) decreased the μ
max from 0.1093 h−1 to 0.0715 h−1. Maximum achievable biodegradation rates of propanol and IPA were 6.11 × 10−3% (v/v) h−1 and 2.72 × 10−3% (v/v) h−1, respectively. Generation of acetone during IPA biodegradation commenced at 264 h and reached a maximum concentration of
0.4% (v/v). The results demonstrate the potential of mixed microbial consortia in the bioremediation of solvent-containing
waste streams.
Received: 14 December 1999 / Received revision: 3 April 2000 / Accepted: 7 April 2000 相似文献
17.
Lépiz-Aguilar Leonardo Rodríguez-Rodríguez Carlos E. Arias María Laura Lutz Giselle Ulate William 《World journal of microbiology & biotechnology》2011,27(8):1933-1939
Cassava flour (CF), a cost-effective source of starch, was employed as a substrate for successful acetone-butanol-ethanol
(ABE) production by batch-fermentation with Clostridium beijerinckii. The effect of temperature, initial concentration of CF and chemical/enzymatic hydrolysis were studied in a 23 factorial design. Results revealed that temperature and initial concentration of substrate exert a significant effect on
ABE production, as well as interactions of temperature with the other variables. Solvent production was maximized when working
at 40°C, 60 g l−1 CF and enzymatic pretreatment. An average of 31.38 g l−1 ABE was produced after 96 h, with a productivity of 0.33 g l−1 h−1. A posterior randomized block design (3 × 2) showed that enzymatic hydrolysis (with saccharification periods of 6 h at 60°C)
enhances both reducing sugar and solvent production if compared to chemical pretreatments. Average ABE production in this
case was 27.28 g l−1, with a productivity of 0.28 g l−1 h−1. Results suggest that CF may be a suitable substrate for industrial ABE production. 相似文献
18.
Vogelaar JC Klapwijk B Temmink H van Lier JB 《Journal of industrial microbiology & biotechnology》2003,30(2):81-88
Kinetic parameters describing growth and decay of mesophilic (30°C) and thermophilic (55°C) aerobic biomass were determined
in continuous and batch experiments by using oxygen uptake rate measurements. Biomass was cultivated on a single soluble substrate
(acetate) in a mineral medium. The intrinsic maximum growth rate (μ
max) at 55°C was 0.71±0.09 h−1, which is 1.5 times higher than the μ
max at 30°C (0.48±0.11 h−1). The biomass decay rates increased from 0.004 h−1 at 30°C to 0.017 h−1 at 55°C. Monod constants were very low for both types of biomass: 9±2 mg chemical oxygen demand (COD) l−1at 30°C and 3±2 mg COD l−1at 55°C. Theoretical biomass yields were similar at 30 and 55°C: 0.5 g biomass COD (g acetate COD)−1. The observed biomass yields decreased under both temperature conditions as a function of the cell residence time. Under
thermophilic conditions, this effect was more pronounced due to the higher decay rates, resulting in lower biomass production
at 55°C compared to 30°C.
Electronic Publication 相似文献
19.
In January 2004 the microplankton community from the coastal waters of Terre Adélie and Georges V Land (139°E–145°E) was studied.
Results showed a diatom-dominated bloom with chlorophyll a levels averaging 0.64 μg l−1 at 5 m depth (range 0.21–1.57 μg l−1). Three geographic assemblages of diatoms were identified, based on principal diatom taxa abundances. The stratified waters
near the Mertz Glacier presented highest phytoplankton biomasses (0.28–1.57 μg Chl a l−1 at 5 m) and diatom abundances (6,507–70,274 cells l−1 at 5 m), but low diversity, dominated by Fragilariopsis spp. Lower biomasses (0.38–0.94 μg Chl a l−1 at 5 m) and abundances (394–9,058 cells l−1 at 5 m) were observed in the mixed waters around the Astrolabe Glacier with a diverse diatom community characterised by larger
species Corethron pennatum and Rhizosolenia spp. Finally an intermediate zone between them over the shallower shelf waters of the Adélie Bank represented by Chaetoceros criophilus, where biomasses (0.21–0.35 μg Chl a l−1 at 5 m) and abundances (1,190–5,431 cells l−1 at 5 m) were lowest, coinciding with the presence of abundant herbivorous zooplankton. 相似文献
20.
Gao Z Li Z Zhang Y Huang H Li M Zhou L Tang Y Yao B Zhang W 《Biotechnology letters》2012,34(3):507-514
The glucose oxidase (GOD) gene from Penicillium notatum was expressed in Pichia pastoris. The 1,815 bp gene, god-w, encodes 604 amino acids. Recombinant GOD-w had optimal activity at 35–40°C and pH 6.2 and was stable, from pH 3 to 7 maintaining >75%
maximum activity after incubation at 50°C for 1 h. GOD-w worked as well as commercial GODs to improve bread making. To achieve
high-level expression of recombinant GOD in P. pastoris, 272 nucleotides involving 228 residues were mutated, consistent with the codon bias of P. pastoris. The optimized recombinant GOD-m yielded 615 U ml−1 (2.5 g protein l−1) in a 3 l fermentor—410% higher than GOD-w (148 U ml−1), and thus is a low-cost alternative for the bread baking industry. 相似文献