Fruits as Prospective Reserves of bioactive Compounds:A Review

Astaxanthin is a value-added ketocarotenoid with great potential in nutraceutical and pharmaceutical industries.Genetic engineering of heterologous hosts for astaxanthin production has attracted great attention.In this study,we assessed some key factors,including codon usage of the expressed genes,types of promoters,bacterial strains,and culture media,for engineered Escherichia coli to produce astaxanthin.The effect of codon usage was shown to be related to the types of promoters.E.coli DH5a was superior to other strains for astaxanthin production.Different culture media greatly affected the contents and yields of astaxanthin in engineered E.coli.When the expression cassette containing GadE promoter and its driving genes,HpCHY and CrBKT,was inserted into the plasmid pACCAR16DcrtX and expressed in E.coli DH5a,the engineered strain was able to produce 4.30±0.28 mg/g dry cell weight(DCW)or 24.16±2.03 mg/L of astaxanthin,which was a sevenfold or 40-fold increase over the initial production of 0.62±0.03 mg/g DCW or 0.61±0.05 mg/L.

Candidate genes for male and female reproductive traits in Canchim beef cattle

Background： Beef cattle breeding programs in Brazil have placed greater emphasis on the genomic study of reproductive traits of males and females due to their economic importance. In this study, genome-wide associations were assessed for scrotal circumference at 210 d of age, scrotal circumference at 420 d of age, age at first calving, and age at second calving, in Canchim beef cattle. Data quality control was conducted resulting in 672,778 SNPs and 392 animals.Results： Associated SNPs were observed for scrotal circumference at 420 d of age（435 SNPs）, followed by scrotal circumference at 210 d of age（12 SNPs）, age at first calving（six SNPs）, and age at second calving（four SNPs）. We investigated whether significant SNPs were within genic or surrounding regions. Biological processes of genes were associated with immune system, multicellular organismal process, response to stimulus, apoptotic process, cellular component organization or biogenesis, biological adhesion, and reproduction.Conclusions： Few associations were observed for scrotal circumference at 210 d of age, age at first calving, and age at second calving, reinforcing their polygenic inheritance and the complexity of understanding the genetic architecture of reproductive traits. Finding many associations for scrotal circumference at 420 d of age in various regions of the Canchim genome also reveals the difficulty of targeting specific candidate genes that could act on fertility; nonetheless,the high linkage disequilibrium between loci herein estimated could aid to overcome this issue. Therefore, al relevant information about genomic regions influencing reproductive traits may contribute to target candidate genes for further investigation of causal mutations and aid in future genomic studies in Canchim cattle to improve the breeding program.

Operculina and Neoassilina:A Revision of Recent Nummulitid Genera Based on Molecular and Morphological Data Reveals a New Genus

The genus Operculina,a large symbiont-bearing benthic foraminifer,is characterized by high morphological variability showing thick involute to intermediate semi-involute to flat evolute tests.Different morphotypes are either considered as ecophenotypes or distinct species.In order to test the hypothesis of ecophenotypes versus different species,a single cell high throughput sequencing approach was applied to assess the interspecific diversity of Operculina.This results in two groups of ribotypes,one corresponding to Operculina ammonoides/Operculina discoidalis,the other containing Operculina complanata/Operculina elegans.These groups can also be separated morphologically.Therefore,O.complanata and O.elegans represent a single species and the latter can be regarded as a junior synonym of O.complanata.Operculina ammonoides and O.discoidalis also form a single species,which makes the latter a junior synonym of O.ammonoides.Because generic differences in Operculina species are manifested in morphology and molecular genetics,the genus Neoassilina with the designated species Neoassilina ammonoides is installed.Additional analysis of ribosomal SSU rDNA data of eight recent nummulitid genera confirms the obtained high troughput sequencing results and further shows that Palaeonummulites venosus builds a clade with O.complanata that branches at the base of other Nummulitidae containing Planostegina,Planoperculina,Cycloclypeus,Heterostegina,Operculinella and Neoassilina.