Natural nano-hydroxyapatite(HA)was extracted from Pacific cod(Gadus macrocephalus)bone with a thermostable col-lagenolytic protease in the present study.Conditions for the enzymatic reaction were optimized to be 60℃a...Natural nano-hydroxyapatite(HA)was extracted from Pacific cod(Gadus macrocephalus)bone with a thermostable col-lagenolytic protease in the present study.Conditions for the enzymatic reaction were optimized to be 60℃and pH 7.0,and a desir-able extraction efficiency was achieved by using the crude collagenolytic protease.Dynamic light scattering,transmission electron microscopy and energy-dispersive X-ray analysis revealed that nano-HA are anionic spherical(about 110nm)particles mainly com-prised of calcium and phosphorus at an approximate ratio of 5:3.As evaluated with the mouse ex vivo intestinal segments,the extracted nano-HA displayed comparable level of intestinal bioavailability to the positive control CaCl_(2).By treating with inhibitors(NaN3,ami-loride)and low temperature(4℃),clathrin-mediated endocytosis was assumed to involve the intestinal absorption of nano-HA.Over-all,the application of thermostable collagenolytic protease is proved to be a promising alternative method for nano-HA extraction from natural resource with improved ecological and biological value.展开更多
Objective:To detect single nucleotide polymorphisms(SNPs)in the cod transferrin gene by comparing the sequences from Norwegian(North East Atlantic Ocean)and Canadian(North West Atlantic Ocean)specimen,and to quantify ...Objective:To detect single nucleotide polymorphisms(SNPs)in the cod transferrin gene by comparing the sequences from Norwegian(North East Atlantic Ocean)and Canadian(North West Atlantic Ocean)specimen,and to quantify the genetic variation and differentiation in East and West Atlantic cod populations.Methods:cDNA sequences between individuals of Canadian(North West Atlantic Ocean)and Norwegian(North East Atlantic Ocean)origin were aligned.Allele frequencies of the SNPs were used to discriminate the different Atlantic cod populations in West/East Atlantic Ocean,and the Baltic Sea.Results:The sequence alignment detected 19 SNPs,of which 18 of them resulted in amino acid changes in the transferrin protein.Nonsynonymous to synonymous site substitution ratio(dn/ds)was by far greater than 1 providing an evidence for the existence of positive selection.The West Atlantic cod populations showed high values of heterozygosity and the Baltic populations were found to be inbred.Conclusions:This study identified and indicated transferrin gene polymorphisms that can be used for population differentiations.展开更多
基金supported by the Natural Science Foundation of Shandong Province(No.ZR202102270334)the National Key Research and Development Program of China(No.2020YFD0901004).
文摘Natural nano-hydroxyapatite(HA)was extracted from Pacific cod(Gadus macrocephalus)bone with a thermostable col-lagenolytic protease in the present study.Conditions for the enzymatic reaction were optimized to be 60℃and pH 7.0,and a desir-able extraction efficiency was achieved by using the crude collagenolytic protease.Dynamic light scattering,transmission electron microscopy and energy-dispersive X-ray analysis revealed that nano-HA are anionic spherical(about 110nm)particles mainly com-prised of calcium and phosphorus at an approximate ratio of 5:3.As evaluated with the mouse ex vivo intestinal segments,the extracted nano-HA displayed comparable level of intestinal bioavailability to the positive control CaCl_(2).By treating with inhibitors(NaN3,ami-loride)and low temperature(4℃),clathrin-mediated endocytosis was assumed to involve the intestinal absorption of nano-HA.Over-all,the application of thermostable collagenolytic protease is proved to be a promising alternative method for nano-HA extraction from natural resource with improved ecological and biological value.
文摘Objective:To detect single nucleotide polymorphisms(SNPs)in the cod transferrin gene by comparing the sequences from Norwegian(North East Atlantic Ocean)and Canadian(North West Atlantic Ocean)specimen,and to quantify the genetic variation and differentiation in East and West Atlantic cod populations.Methods:cDNA sequences between individuals of Canadian(North West Atlantic Ocean)and Norwegian(North East Atlantic Ocean)origin were aligned.Allele frequencies of the SNPs were used to discriminate the different Atlantic cod populations in West/East Atlantic Ocean,and the Baltic Sea.Results:The sequence alignment detected 19 SNPs,of which 18 of them resulted in amino acid changes in the transferrin protein.Nonsynonymous to synonymous site substitution ratio(dn/ds)was by far greater than 1 providing an evidence for the existence of positive selection.The West Atlantic cod populations showed high values of heterozygosity and the Baltic populations were found to be inbred.Conclusions:This study identified and indicated transferrin gene polymorphisms that can be used for population differentiations.