• The Korean Journal of Pharmacology
• /
• v.15 no.1_2 s.25
• /
• pp.1-5
• /
• 1979

Previous studies concerning the usefulness of pleural fluid glucose levels in differentiating causes of pleural effusions have been conflicting. Gelenger and Wiggers (1949), Calnan et al(1951) and Barber et al(1957) concluded that the lower the level of pleural fluid glucose, the more likely was tuberculosis, and that tuberculosis was unlikely if the pleural fluid glucose level was more than 80 mg/100 ml. Light and Ball(1973), however, reported that in the great majority of tuberculous pleural fluids the glucose concentration was high rather than low, concluded that the pleural fluid glucose levels were not useful in the differential diagnosis of pleural effusion. In this study, pleural fluid glucose was determined in 46 pleural effusions from various causes to evaluate the usefulness in the differential diagnosis of pleural effusion. In addition, the protein concentration and the electrophoretic patterns of protein and amylases in pleural fluid was compared with that of serum. And the results were as follows. 1. The mean glucose concentration of pleural fluid was 80.8 mg/100 ml in 22 tuberculous origin, 92.5 mg/100 ml in 12 cancer patient and 70.4 mg/100 ml in 10 undiagnosed cases. In 2 cases of paragonimiasis the pleural fliud glucose levels were low (mean, 32.0 mg/100 ml). The percentage of pleural fluid protein to serum is about 75% in all disease groups and the protein level of tuberculous pleural fluid was significantly correlated with that of serum. 2. The disc eletrophoretic patterns of pleural fluid were almost similar with that of serum in all disease groups but the prealbumin fraction was not observed in pleural fluid. 3. With the isoelectric focusing, 4 to 7 isoamylase was observed in serum and the isoelectric point was ranged from pH 5.8 to 7.8 and isoelectic point of main fracticn is pH 7.2. The isoelectic focusing patterns of amylase of pleural fluid were identical to that of serum in all disease group. With the above results it is concluded that the pleural fluid is exudate of serum and that the glucose levels of pleural fluid are not useful in the differential diagnosis of pieural effusions.

• Korean Journal of Food Science and Technology
• /
• v.48 no.4
• /
• pp.341-346
• /
• 2016

The AMY2B gene, encoding human pancreatic ${\alpha}$-amylase isozyme (HPA II), was expressed in Pichia pastoris, and the effects of chloride ions on HPA II activity toward starch substrates were investigated. As seen with chloride ion-dependent ${\alpha}$-amylases-including HPA I, the isozyme of HPA II-chloride ions increased enzyme activity and shifted the optimal pH to an alkaline pH. The activity enhancement by chloride was more significant at pH 8 than that at pH 6, suggesting that the protonation state of the general acid/base catalyst of HPA II was important for the hydrolysis of starches at an alkaline pH because of the increase in its $pK_a$ by chloride ions. The turnover values for cereal starches as the substrates markedly increased in the presence of chloride by up to 7.2-fold, whereas that for soluble starch increased by only 1.7-fold. Chloride inhibited substrate hydrolysis at high substrate concentrations, with $K_i$ values ranging from 6 to 15 mg/mL.

• BMB Reports
• /
• v.40 no.3
• /
• pp.315-324
• /
• 2007

The novel $\alpha$-amylase purified from locally isolated strain, Bacillus sp. KR-8104, (KRA) (Enzyme Microb Technol; 2005; 36: 666-671) is active in a wide range of pH. The enzyme maximum activity is at pH 4.0 and it retains 90% of activity at pH 3.5. The irreversible thermoinactivation patterns of KRA and the enzyme activity are not changed in the presence and absence of $Ca^{2+}$ and EDTA. Therefore, KRA acts as a $Ca^{2+}$-independent enzyme. Based on circular dichroism (CD) data from thermal unfolding of the enzyme recorded at 222 nm, addition of $Ca^{2+}$ and EDTA similar to its irreversible thermoinactivation, does not influence the thermal denaturation of the enzyme and its Tm. The amino acid sequence of KRA was obtained from the nucleotide sequencing of PCR products of encoding gene. The deduced amino acid sequence of the enzyme revealed a very high sequence homology to Bacillus amyloliquefaciens (BAA) (85% identity, 90% similarity) and Bacillus licheniformis $\alpha$-amylases (BLA) (81% identity, 88% similarity). To elucidate and understand these characteristics of the $\alpha$-amylase, a model of 3D structure of KRA was constructed using the crystal structure of the mutant of BLA as the platform and refined with a molecular dynamics (MD) simulation program. Interestingly enough, there is only one amino acid substitution for KRA in comparison with BLA and BAA in the region involved in the calcium-binding sites. On the other hand, there are many amino acid differences between BLA and KRA at the interface of A and B domains and around the metal triad and active site area. These alterations could have a role in stabilizing the native structure of the loop in the active site cleft and maintenance and stabilization of the putative metal triad-binding site. The amino acid differences at the active site cleft and around the catalytic residues might affect their pKa values and consequently shift its pH profile. In addition, the intrinsic fluorescence intensity of the enzyme at 350 nm does not show considerable change at pH 3.5-7.0.

• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.9
• /
• pp.1334-1340
• /
• 2002

A 4 week experiment was designed to study the effects of replacing corn with Chinese brown rice or adding different amylase in brown rice basal diet on growth performance and apparent fecal digestibilities of nutrients in growing pigs. One hundred and eight cross-bred pigs (Duroc${\times}$Landrace${\times}$Large White), weighing an average of $18.35{\pm}0.12kg$, were randomly assigned to 6 treatments with 6 replications per treatment. Diet in treatment 1 was corn-soybean meal basal diet, and in treatment 2, 3 and 4, corn was replaced by brown rice on rates of 33.3%, 66.7% and 100% respectively on the basis of treatment 1. And diets in treatment 5 and 6 were similar to treatment 4 except two kinds of amylases, glucoamylase and ${\alpha}$-amylase, were added respectively. The brown rice used in this experiment was husked from one kind of early, long grain, non-glutinous rice (ELGNR, indica rice) in southern China. The results indicated that there was a slight improvement in growth performance of pigs in brown rice treatments (p>0.05). The blood urea nitrogen value in treatment 2 was lower than that in treatment 1 (p<0.05). The differences of apparent fecal digestibilities of most nutrients were significant (p<0.05) except CP. Digestibilities of GE, OM and DM in treatment 4 were the best and digestibility of crude fat in treatment 5 appeared best (p<0.05). Contrast results between treatment 1 and treatment 2 to 4 indicated that the digestibility of GE, OM and DM increased significantly with the replacing rates of brown rice (p<0.05). Contrast results between treatment 4 and 5 indicated that adding glucoamylase in brown rice diet increased growth performance slightly (p>0.05) but not for digestibilities. This experiment shows a positive effect of brown rice on growth performance, especially on nutrient digestibility.

• Korean Journal of Food Science and Technology
• /
• v.40 no.3
• /
• pp.290-296
• /
• 2008

This study examined the physicochemical properties of chemically and enzymatically cross-modified waxy rice starches. The waxy rice starch was cross-linked using phosphorous oxychloride, and then partially hydrolyzed with four commercial ${\alpha}$-amylases (Fungamyl, Termamyl, Liquozyme, Kleistase). Swelling power and the moisture sorption isotherm did not change with cross-modification. Two cross-modified waxy rice starches (hydrolyzed with Termamyl and Liquozyme) showed higher solubilities than native starch and the two other cross-modified starches (hydrolyzed with Fungamyl and Kleistase). In terms of RVA characteristics, the two cross-modified waxy rice starches hydrolyzed with Termamyl and Liquozyme, respectively, had lower peak viscosity, holding strength, and final viscosity than the native starch. However, the two starches hydrolyzed with Fungamyl and Kleistase, respectively, revealed higher peak viscosity, holding strength, and final viscosity than the native starch. No differences were displayed in the X-ray diffraction patterns and DSC thermal characteristics of the cross-modified waxy rice starch as compared to both the native and cross-linked starches, indicating that cross-linking and enzymatic hydrolysis occurred in the amorphous region and did not alter the crystalline region.

• Korean Journal of Food Science and Technology
• /
• v.29 no.5
• /
• pp.901-906
• /
• 1997

In order to reproduce and improve quality of traditional kochujang, various raw materials were added to prepare kochujang by replacing part of the glutinous rice. Chemical composition, microbial characteristics and enzyme activities were investigated during fermentation. Crude protein and salt contents of kochujang did not change significantly during fermentation, but moisture contents increased linearly. The pH and titratable acidity of kochujang changed little in garlic added group. The viable cell counts of aerobic bacteria and yeasts in the kochujang increased until 60 days of fermentation and then decreased slowly except for the garlic added group in which they increased during the last period of fermentation. Aerobic bacterial count did not show any remarkable differences among the samples and slowly decreased after 60 days of fermentation. The activities of liquefying and saccharifying amylases decreased until 45 days, but increased at 60th day. Acidic protease activities of each group were strong during the initial period, but neutral protease showed the highest activity from the 30 to 45 days of fermentation. Protease activities increased by addition of soy sauce, Chinese matrimony vine and purple sweet potato.

• Microbiology and Biotechnology Letters
• /
• v.38 no.2
• /
• pp.151-157
• /
• 2010

Barley malt produces two different $\alpha$-amylase isozymes (AMY1 and AMY2), which share up to 80% of amino acid sequence identity with each other. However, their enzymatic properties differ remarkably. In this study, five chimeric enzymes between AMY1 and 2 were constructed by staggered extension process (StEP) technique, and their enzymatic properties were characterized. According to the results, chimeric AMY-D2, D8, and E12 showed the mixed or intermediate types of calcium-dependent activity between AMY1 and 2. Meanwhile, only AMY-E10 chimera could be significantly inhibited by barley $\alpha$-amylase/subtilisin inhibitor (BASI) protein. Chimera AMY-C6 showed the same calcium-dependency as AMY1, while AMY-E10 was closely similar to AMY2. As a result, it can be proposed that some amino acid residues in the region II, III, and IV of barley $\alpha$-amylases can play very important roles in the interaction with BASI, and those in III, V, VI, and VII may partly affect on the calcium-dependent activity.

• The Korean Journal of Mycology
• /
• v.6 no.2
• /
• pp.1-10
• /
• 1978

In de novo biosynthesis of the extracellulor enzymes-proteinsaes, alpha and gluc-amylases during the synchronized differentiation of Aspergillus niger in submerged culture and surface liquid culture were investigated. Gluc-amylase was synthesized in the stage of presporulation in which phialide formation is involved. Proteinase was synthesized both in the stages of conidiophore formation and presporulation. Alpha-amylase was synthesized during presporulation and sporulation stages, the activity of enzyme lasted for seven days on surface liquid culture. It seemed that the synthesis was occured in de novo partly repressed by the catabolite, and its nature was found to be constitutive since it is produced in non-starch medium. Polyacrylamide gel electrophoresis have shown that presporulating and sporulating body produced diverse types of the proteins whereas the earlier stages of vegetative body showed simpler profiles. The uptake of C-14 uracil into RNA and C-14 glutamate into protein were shown to be vigorous in presporulating body rather than those in sporulating body. Coincidence of alpha-amylase biosynthesis in de novo and sporulation may be significant in the study of differentiation in which gene expression is involved.

• Journal of Life Science
• /
• v.33 no.10
• /
• pp.808-819
• /
• 2023

This study was conducted to develop a selection marker for the identification of the Bacillus licheniformis K12 strain in microbial communities. The strain not only demonstrates good growth at moderate temperatures but also contains enzymes that catalyze the decomposition of various polymer materials, such as proteases, amylases, cellulases, lipases, and xylanases. To identify molecular markers appropriate for use in a microbial community, a search was conducted to identify variable gene regions that show considerable genetic mutations, such as recombinase, integration, and transposase sites, as well as phase-related genes. As a result, five areas were identified that have potential as selection markers. The candidate markers were two recombinase sites (BLK1 and BLK2), two integration sites (BLK3 and BLK4), and one phase-related site (BLK5). A PCR analysis performed with different Bacillus species (e.g., B. licheniformis, Bacillus velezensis, Bacillus subtilis, and Bacillus cereus) confirmed that PCR products appeared at specific locations in B. licheniformis: BLK1 in recombinase, BLK2 in recombinase family protein, and BLK3 and BLK4 as site-specific integrations. In addition, BLK1 and BLK3 were identified as good candidate markers via a PCR analysis performed on subspecies of standard B. licheniformis strains. Therefore, the findings suggest that BLK1 can be used as a selection marker for B. licheniformis species and subspecies in the microbiome.