Specific DNA barcodes screening, germplasm resource identification, and genetic diversity analysis of Platycodon grandiflorum / 药学学报

Platycodonis Radix is the dry root of Platycodon grandiflorum of Campanulaceae, which has a variety of pharmacological effects and is a commonly used bulk Chinese medicine. In this study, the chloroplast genome sequences of six P. grandiflorum from different producing areas has been sequenced with Illumina HiSeq X Ten platform. The specific DNA barcodes were screened, and the germplasm resources and genetic diversity were analyzed according to the specific barcodes. The total length of the chloroplast genome of 6 P. grandiflorum samples was 172 260-172 275 bp, and all chloroplast genomes showed a typical circular tetrad structure and encoded 141 genes. The comparative genomics analysis and results of amplification efficiency demonstrated that trnG-UCC and ndhG_ndhF were the potential specific DNA barcodes for identification the germplasm resources of P. grandiflorum. A total of 305 P. grandiflorum samples were collected from 15 production areas in 9 provinces, for which the fragments of trnG-UCC and ndhG_ndhF were amplificated and the sequences were analyzed. The results showed that trnG-UCC and ndhG_ndhF have 5 and 11 mutation sites, respectively, and 5 and 7 haplotypes were identified, respectively. The combined analysis of the two sequences formed 13 haplotypes (named Hap1-Hap13), and Hap4 is the main genotype, followed by Hap1. The unique haplotypes possessed by the three producing areas can be used as DNA molecular tags in this area to distinguish from the germplasm resources of P. grandiflorum from other areas. The haplotype diversity, nucleotide diversity and genetic distance were 0.94, 4.79×10-3 and 0.000 0-0.020 3, respectively, suggesting that the genetic diversity was abundant and intraspecific kinship was relatively close. This study laid a foundation for the identification of P. grandiflorum, the protection and utilization of germplasm resources, and molecular breeding.

A Rapid PCR-RFLP Method for Assessing Heterozygosity of Murraya paniculata Germplasm / 中国实验方剂学杂志

ObjectiveTo establish a rapid method for evaluating the heterozygosity of Murraya paniculata germplasm materials and provide as a foundation for developing germplasm breeding and innovation measures for M. paniculata. MethodSingle nucleotide polymorphisms （SNPs） were screened from the genome resequencing data of 65 plants of M. paniculata. A self-written script was used to transform 20 SNPs into restriction fragment length polymorphism （RFLP） markers. Polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） was employed to detect the 20 RFLP markers in 12 M. paniculata germplasm accessions， and the heterozygosity of M. paniculata germplasm accessions was calculated based on the number of enzyme-cutting bands at the 20 RFLP marker sites. Plink was used to calculate the whole genome heterozygosity of 12 M. paniculata germplasm accessions， and the results obtained with different methods were compared. ResultThere was no significant difference in the heterozygosity calculated by the PCR-RFLP method and the genome resequencing method. The PCR-RFLP and genome resequencing methods identified 8 and 9 germplasm accessions， respectively， with a heterozygosity level less than 30%. Seven germplasm accessions with heterozygosity less than 30.00% were calculated by both methods. ConclusionThe PCR-RFLP method established in this study for evaluating the heterozygosity of M. paniculata germplasm demonstrates the precision of 87.5% and the accuracy of 77.8%. This method serves as a reference for developing heterozygosity evaluation methods in other medicinal plant germplasm resources.

La viruela sísmica aspectos relacionados a la fisiopatología, genoma, patogénesis, transmisión, replicación e inmunología / Aspects Related to pathophysiology, Genome, Pathogenesis, Transmission, Replication and Immunology of Monkeypox

Introducción: La viruela símica es una enfermedad zoonótica identificada por primera vez en 1958. El virus es un miembro del género Orthopoxvirus, de la familia Poxviridae. Infecta a una amplia variedad de mamíferos y se desconoce su reservorio natural. Objetivos: Describir los aspectos importantes relacionados a la fisiopatología, genoma, patogénesis, transmisión, replicación e inmunología de la viruela símica. Métodos: Se realizó una búsqueda de artículos originales, reportes de casos, revisiones bibliográficas y sistemáticas en el Portal Regional de la BVS, PubMed, Science, Nature y Lancet. Se consultaron los informes de la Organización Mundial de la Salud y la Organización Panamericana de la Salud sobre la viruela símica. Resultados: La propagación del virus de la viruela símica puede ocurrir a través del contacto cercano con lesiones, fluidos corporales, gotitas respiratorias y objetos contaminados. Una vez dentro del organismo, el virus infecta mucosas, células epiteliales y células inmunitarias de los tejidos adyacentes. El virus se replica y disemina rápidamente a través del sistema hemático y linfático. Las células T desempeñan un papel importante en la regulación de la respuesta inmunitaria contra el virus. Sin embargo, los Orthopoxvirus han desarrollado varios mecanismos para la evasión de la respuesta inmunitaria. Conclusiones: Los aspectos importantes descritos que se tuvieron en cuenta acerca de la transmisión de la viruela símica han tenido cambio significativo con el tiempo. El brote mundial de viruela símica de 2022 presentó una cadena de transmisión principalmente entre humanos asociada al contacto sexual(AU).

Introduction: Monkeypox is a zoonotic disease that was first identified in 1958. The virus is a member of Orthopoxvirus genus, of Poxviridae family. It infects wide variety of mammals and its natural reservoir is unknown. Objectives: To describe the important aspects related to pathophysiology, genome, pathogenesis, transmission, replication and immunology of monkeypox. Methods: A search of original articles, case reports, bibliographic and systematic reviews was carried out in VHL Regional Portal, PubMed, Science, Nature and Lancet. Reports from the World Health Organization and the Pan American Health Organization on monkeypox were consulted. Results: Spread of monkeypox virus can occur through close contact with lesions, body fluids, respiratory droplets, and contaminated objects. Once inside the body, the virus infects mucous membranes, epithelial cells and immune cells of adjacent tissues. The virus replicates and spreads rapidly through the blood and lymphatic system. T cells play an important role in regulating the immune response against the virus. However, Orthopoxviruses have developed several mechanisms to evade the immune response. Conclusions: The important aspects described, taken into account about monkeypox transmission, have significantly changed over time. 2022 global monkeypox outbreak presented a chain of transmission primarily among humans associated with sexual contact(AU)

Candida auris: a global pathogen that has taken root in Colombia

Candida auris has been recognized as an emerging multidrug-resistant pathogen with a significant public health burden, causing cases of invasive infection and colonization due to its persistence on inanimate surfaces, ability to colonize skin of some patients, and high transmissibility in healthcare settings. The first sporadic report of the isolation of this species from the ear canal of a patient in Asia was in 2009 and reports from other regions of the world soon followed. However, it was not until 2015 that global epidemiological alerts were communicated as a result of an increasing number of reports of invasive infections caused by C. auris in several countries. Colombia was soon added to this list in 2016 after an unusual increase in the number of C. haemulonii isolates was reported, later confirmed as C. auris. Since the issuing of a national alert by the Colombian National Institute of Health together with the Ministry of Health in 2016, the number of cases reported reached over 2,000 by 2022. Colombian isolates have not shown pan resistance to available antifungals, unlike C. auris strains reported in other regions of the world, which leaves patients in Colombia with therapeutic options for these infections. However, increasing fluconazole resistance is being observed. Whole-genome sequencing of Colombian C. auris isolates has enhanced molecular epidemiological data, grouping Colombian isolates in clade IV together with other South American isolates. Data from Colombia showed that public health authorities, scientific community, and the general public need to be aware of fungal diseases as they present an often-deadly threat to patients.

Candida auris ha sido reconocido como un agente patógeno multirresistente emergente con una carga significativa en la salud pública. Genera casos de infección invasiva y colonización debido a su persistencia en superficies inanimadas, su capacidad para colonizar fácilmente la piel de algunos pacientes y su alta transmisibilidad en el ambiente hospitalario. El primer reporte esporádico de esta especie fue en Asia en el 2009 cuando se realizó su aislamiento a partir del conducto auditivo de un paciente, y pronto le siguieron reportes en otras regiones del mundo. Sin embargo, no fue hasta 2015 que se conocieron las alertas epidemiológicas a nivel mundial debido a un aumento en el número de casos de infecciones causadas por C. auris en varios países. Colombia se sumó a la lista en 2016 luego de un aumento inusual en el número de aislamientos de C. haemulonii informados, que luego se confirmaron como C. auris. Desde que el Instituto Nacional de Salud junto con el Ministerio de Salud emitieron la Alerta Nacional en el 2016, el número de casos reportados superó los 2.000 en el 2022. Los aislamientos colombianos no han mostrado resistencia generalizada a los antifúngicos disponibles, contrario a lo reportado para cepas de C. auris en algunas regiones del mundo, por lo que los pacientes en Colombia aún cuentan con opciones terapéuticas para estas infecciones. No obstante, se ha observado un aumento en la resistencia al fluconazol. La secuenciación del genoma completo agrupó los aislamientos colombianos en el Ciado IV, junto con otros sudamericanos de C. auris, y aportó al conocimiento de los datos epidemiológicos moleculares de esta especie. Los datos de Colombia evidencian que las autoridades de salud pública, la comunidad científica y el público en general deben ser conscientes de las enfermedades fúngicas, ya que a menudo representan una amenaza mortal para los pacientes.

First molecular characterization of Escherichia coli O157:H7 isolates from clinical samples in Paraguay using whole-genome sequencing Molecular characterization of Escherichia coli O157 isolates from Paraguay / Primera caracterización molecular de aislamientos de Escherichia coli O157:H7 provenientes de muestras clínicas en Paraguay utilizando secuenciación de genoma completo

Abstract Escherichia coli O157:H7 is a foodborne pathogen implicated in numerous outbreaks worldwide that has the ability to cause extra-intestinal complications in humans. The Enteropathogens Division of the Central Public Health Laboratory (CPHL) in Paraguay is working to improve the genomic characterization of Shiga toxin-producing E. coli (STEC) to enhance laboratory-based surveillance and investigation of foodborne disease outbreaks. Whole genome sequencing (WGS) is proposed worldwide to be used in the routine laboratory as a high-resolution tool that allows to have all the results in a single workflow. This study aimed to carry out for the first time, the genomic characterization by WGS of nine STEC O157:H7 strains isolated from human samples in Paraguay. We were able to identify virulence and resistance mechanisms, MLST subtype, and even establish the phylogenetic relationships between isolates. Furthermore, we detected the presence of strains belonging to hypervirulent clade 8 in most of the isolates studied.

Resumen Escherichia coli O157:H7 es un patógeno transmitido por alimentos implicado en numerosos brotes en todo el mundo y es capaz de causar complicaciones extraintestinales en humanos. La sección de «Enteropatógenos¼ del Laboratorio Central de Salud Pública trabaja en mejorar la caracterización genómica de STEC, de modo de potenciar la vigilancia laboratorial y la investigación de brotes de enfermedades transmitidas por alimentos. La secuenciación de genoma completo (WGS, por sus siglas en inglés) se propone a nivel mundial como una herramienta de alta resolución para ser utilizada en el laboratorio de rutina, ya que permite obtener todos los resultados en un único proceso. El objetivo de este trabajo fue llevar a cabo, por primera vez, la caracterización genómica por WGS de nueve cepas STEC O157:H7 aisladas en Paraguay a partir de muestras de origen humano. Pudimos identificar los factores de virulencia, los mecanismos de resistencia, el subtipo MLST, e incluso pudimos establecer la relación filogenética entre los aislamientos. Además, detectamos que la mayoría de las cepas pertenecían al clado hipervirulento 8.

Advancements in Genetic Diversity and Genome Characteristics of Durians (Durio spp.)

Durian is one of the important fruit crops in Southeast Asia with its unique flavor and important economic benefits. Breeding programs have produced hundreds of different cultivars of durian. These cultivars are classified mainly by fruit and flower characteristics, which cannot be observed at the vegetative stage. Therefore, molecular biology is a powerful tool to approach and explore the genetic characteristics of durians. Many studies based on barcoded DNA and molecular markers have been conducted and valuable data have been exploited. Thanks to the advancement of sequencing technology, the plastid genome and the whole genome were sequenced in some durian cultivars. The data revealed reliable data on the structure and function of several genes. This review aims to update recent studies on the durian genome attributes and potential applications in the conservation of germplasm, authentication, and exploration of the gene structure and function of this specialty plant.

Web-tools for the genomic analysis of the 2022 Monkeypox virus global outbreak / Herramientas web para el análisis genómico del virus de la viruela símica durante el brote mundial de 2022

Abstract The resources and platforms available on the internet for collecting and sharing information and performing genomic sequence analysis have made it possible to follow closely the evolution the evolution of SARS-CoV-2. However, the current monkeypox outbreak in the world brings us back to the need to use these resources to appraise the extent of this outbreak. The objective of this work was an analysis of the information presented so far in the genomic database GISAID EpiPox™, using various tools available on the web. The results indicate that the monkeypox outbreak is referred as MPXV clade II B.1 lineage and sub-lineages, isolated from male patients mainly from the European and American continents. In the current scenario, the access to genomic sequences, epidemiological information, and tools available to the scientific community is of great importance for global public health in order to follow the evolution of pathogens.

Resumen Los recursos y plataformas disponibles en Internet para recopilar, compartir información y realizar análisis de secuencias genómicas han permitido seguir de cerca la evolución del SARS-CoV-2. El actual brote global de viruela del mono en el mundo, requiere de nuevo utilizar estos recursos para conocer el alcance de este brote. El objetivo de este trabajo fue un análisis de la información presentada hasta el momento en la base de datos genómica EpiPox™ de GISAID, utilizando diversas herramientas disponibles en la web. Los resultados indican que el brote de la viruela del mono o símica está referido al linaje y sub-linajes B.1 del clado II de MPXV, aislado principalmente de pacientes hombres de Europa y América. En el escenario actual, el acceso a las secuencias genómicas, la información epidemiológica, y las herramientas disponibles para la comunidad científica son de gran importancia para la salud pública mundial con el fin de seguir la evolución de los patógenos.

Genomic monitoring unveils a high prevalence of severe acute respiratory syndrome coronavirus 2 Omicron variant in vaccine breakthrough cases in Bahia, Brazil

SUMMARY OBJECTIVE: Genome sequencing has been proved to be an excellent tool to monitor the molecular epidemiology of the disease caused by severe acute respiratory syndrome coronavirus 2, i.e., coronavirus disease 2019. Some reports of infected, vaccinated individuals have aroused great interest because they are primarily being infected with circulating variants of concern. To investigate the cases of infected, vaccinated individuals in Salvador, Bahia, Brazil, we performed genomic monitoring to estimate the magnitude of the different variants of concern in these cases. METHODS: Nasopharyngeal swabs from infected (symptomatic and asymptomatic), vaccinated or unvaccinated individuals (n=29), and quantitative reverse transcription polymerase chain reaction cycle threshold value (Ct values) of ≤30 were subjected to viral sequencing using nanopore technology. RESULTS: Our analysis revealed that the Omicron variant was found in 99% of cases and the Delta variant was found in only one case. Infected, fully vaccinated patients have a favorable clinical prognosis; however, within the community, they become viral carriers with the aggravating factor of viral dissemination of variants of concern not neutralized by the currently available vaccines. CONCLUSION: It is important to acknowledge the limitations of these vaccines and to develop new vaccines to emergent variants of concern, as is the case of influenza vaccine; going through new doses of the same coronavirus vaccines is "more of the same."

Viruela símica: una revisión narrativa de la fisiopatología

La viruela símica es una enfermedad zoonótica identificada por primera vez en 1958. El virus es un miembro del género Orthopoxvirus, de la familia Poxviridae. Infecta a una amplia variedad de mamíferos, pero se desconoce su reservorio natural. El virus del brote de 2022 pertenece a los clados IIa y IIb. Es probable que la aparición del brote actual se deba a las importaciones del brote de Nigeria de 2017-2018. La propagación de persona a persona puede ocurrir a través del contacto cercano con lesiones, fluidos corporales, gotitas respiratorias y objetos contaminados. Una vez dentro del organismo, el virus infecta las mucosas, células epiteliales y células inmunitarias de los tejidos adyacentes. Luego, el virus se replica y disemina rápidamente a través del sistema hemático y linfático. Las células T desempeñan un papel importante en la regulación de la respuesta inmunitaria contra el virus. Sin embargo, los Orthopoxvirus han desarrollado varios mecanismos para la evasión de la respuesta inmunitaria. La vigilancia de la enfermedad es un factor crucial en la evaluación de riesgo del virus y del control del brote. Para esta revisión se realizó la búsqueda de los principales artículos relacionados a la patogenia del virus, publicados hasta la fecha. El artículo destaca la necesidad de nuevos estudios sobre transmisibilidad y patogenicidad de las cepas asociadas al brote de 2022.

Monkeypox is a zoonotic disease first identified in 1958. The virus is a member of the genus Orthopoxvirus, family Poxviridae. It infects a wide variety of mammals, but its natural reservoir is unknown. The virus in the 2022 outbreak belongs to clades IIa and IIb. The emergence of the current outbreak is likely to be due to importations from the 2017-2018 Nigerian outbreak. Person to person spread can occur through close contact with lesions, body fluids, respiratory droplets and contaminated objects. Once inside the body, the virus infects mucous membranes, epithelial cells and immune cells in adjacent tissues. The virus then replicates and spreads rapidly through the blood and lymphatic system. Tcells play an important role in regulating the immune response against the virus. However, Orthopoxvirus have evolved several mechanisms for evasion of the immune response. Disease surveillance is a crucial factor in virus risk assessment and outbreak control. For this review we searched for the main articles related to the pathogenesis of the virus published to date. The article highlights the need for further studies on transmissibility and pathogenicity of the strains associated with the 2022 outbreak.

The dynamics of genome size and GC contents evolution in genus Nicotiana / A dinâmica do tamanho do genoma e a evolução dos conteúdos de GC no gênero Nicotiana

Abstract Hybridization and Polyploidization are most common of the phenomenon observed in plants, especially in the genus Nicotiana leading to the duplication of genome. Although genomic changes associated with these events has been studied at various levels but the genome size and GC content variation is less understood because of absence of sufficient genomic data. In this study the flow cytometry technique was used to uncover the genome size and GC contents of 46 Nicotiana species and we compared the genomic changes associated with the hybridization events along evolutionary time scale. The genome size among Nicotiana species varied between 3.28 pg and 11.88 pg whereas GC contents varied between 37.22% and 51.25%. The tetraploid species in genus Nicotiana including section Polydiclae, Repandae, Nicotiana, Rustica and Sauveolentes revealed both up and downsizing in their genome sizes when compared to the sum of genomes of their ancestral species. The genome sizes of three homoploid hybrids were found near their ancestral species. Loss of large genome sequence was observed in the evolutionary more aged species (>10 Myr) as compared to the recently evolved one's (<0.2 Myr). The GC contents were found homogenous with a mean difference of 2.46% among the Nicotiana species. It is concluded that genome size change appeared in either direction whereas the GC contents were found more homogenous in genus Nicotiana.

Resumo A hibridização e a poliploidização são os fenômenos mais comuns observados em plantas, principalmente no gênero Nicotiana, levando à duplicação do genoma. Embora as mudanças genômicas associadas a esses eventos tenham sido estudadas em vários níveis, o tamanho do genoma e a variação do conteúdo de GC são menos compreendidos devido à ausência de dados genômicos suficientes. Neste estudo, a técnica de citometria de fluxo foi usada para descobrir o tamanho do genoma e o conteúdo de GC de 46 espécies de Nicotiana, e comparamos as mudanças genômicas associadas aos eventos de hibridização ao longo da escala de tempo evolutiva. O tamanho do genoma entre as espécies de Nicotiana variou entre 3,28 pg e 11,88 pg, enquanto os conteúdos de GC variaram entre 37,22% e 51,25%. As espécies tetraploides do gênero Nicotiana, incluindo as seções Polydiclae, Repandae, Nicotiana, Rustica e Sauveolentes, revelaram aumento e redução do tamanho do genoma quando comparados à soma dos genomas de suas espécies ancestrais. Os tamanhos do genoma de três híbridos homoploides foram encontrados perto de suas espécies ancestrais. A perda da grande sequência do genoma foi observada nas espécies evolutivas mais velhas (> 10 Myr) em comparação com as que evoluíram recentemente (< 0,2 Myr). Os teores de GC foram homogêneos com diferença média de 2,46% entre as espécies de Nicotiana. Conclui-se que a mudança no tamanho do genoma apareceu em ambas as direções, enquanto os conteúdos de GC foram encontrados mais homogêneos no gênero Nicotiana.

Genome-sequence, annotation and phylogenetic insights of the lactic acid bacterium Limosilactobacillus fermentum strain LAB1 obtained from the dairy beverage borhani

Limosilactobacillus fermentum is a promising probiotic with several documented health benefits. LAB1 is an antagonistic L. fermentum strain isolated from borhani, a traditional South Asian beverage prepared from dairy and plant ingredients. Here, I present the genome sequence of the L. fermentum LAB1 strain, its annotation, and phylogenetic features. The 2.01 Mb genome with a G+C content of 51.9% was assembled into 221 contigs and predicted to have 1,913 protein-coding genes, 98 pseudo genes, 7 rRNAs, 60 tRNAs, and 1 CRISPR array. As much as 91.1% of the coding sequences could be assigned to known functional genes. Determination of average nucleotide identity (ANI) of the genome sequence revealed 99.37% identity to that of the type strain ATCC 14931. Its 16S rRNA gene sequence extracted from the genome sequence showed close phylogenetic association with several L. fermentum strains. The genome sequence is expected to provide useful insights with regard to the phenotypic, metabolic and beneficial aspects of this lactic acid bacterium.(AU)

Analysis on the structural changes of intestinal and pulmonary flora in mice with sepsis and acute lung injury / 中华急诊医学杂志

Objective:To investigate the microecological structure changes and correlation in blood, lung tissue and fecal intestine of mice with sepsis and acute lung injury.Methods:A total of 12 healthy male C57BL/6J mice were divided into the cecal ligation and perforation (CLP) group and sham operation (sham) group by random number table method, with six mice in each group. In the CLP group, acute lung injury model of sepsis mice was prepared by CLP method. In the sham group, only laparotomy but no perforation of cecal ligation was performed. Eye blood, lung tissue, and feces were collected from mice in each group 24 h after surgery. Lung tissue morphological changes were observed by HE staining, and 16s ribosome RNA sequencing was used to analyze the structural changes of microecology of the bacterial flora at each site in sepsis mice and find out the correlation.Results:(1) HE staining showed that mice in the CLP group had exudation into the alveolar cavity of the lung, disordered lung tissue structure, accompanied by a large number of inflammatory cell infiltration, and the lung histopathological score was significantly higher than that in the sham group ( P < 0.01). (2)α diversity analysis showed that there was no statistical significance in blood and fecal samples between the sham group and CLP group, while Ace index, Chao index and Simpson index in lung tissue samples were statistically significant ( P < 0.05). (3) β diversity analysis showed that the differences in blood and fecal samples were greater between the sham group and CLP group than that within the group, and analysis of Bray Curtis, weighted, and unweighted indexes were statistically significant ( P < 0.05). (4) At the phylum level, compared with the sham group, the abundance of Proteobacteria gradually increased, and the abundance of Firmicutes and actinobacteria was decreased in the CLP group. At the genus level, the sham group was dominated by Acinetobacter and Duchenne, while the CLP group was dominated by Escherichia coli and unclassified Enterobacter. Blood flora was more similar to lung tissue flora composition as compared with fecal flora. Conclusions:The distribution of bacterial flora in blood, lung tissue and intestine of sepsis mice with acute lung injury is partially overlapped.

Research progress in the etiology of hepatitis type E virus / 中华肝脏病杂志

Hepatitis type E virus (HEV) is a significant infectious zoonotic disease that causes hepatitis E. The disease is primarily transmitted via the fecal-oral route through contaminated water or food and is transmissible between species and genera. The causative agent for the disease is the hepatitis type E virus, which is a member of the Hepadnaviridae family and a single-stranded RNA virus. Its 7.2 kb genome mainly contains three open reading frames (ORFs): ORF1 encodes a non-structural polyprotein that mediates viral replication and transcription; ORF2 encodes a capsid protein and free antigen that induce neutralizing antibodies; ORF3 partially overlaps with ORF2 and encodes a small multifunctional protein involved in virion formation and release. HEV has a unique dual life cycle: it is excreted into feces in the form of naked virions but circulates in the blood in the form of "quasi-enveloped" particles. The two kinds of virus particles adsorb and penetrate the host cell in distinct ways, then internalize and decapsulate to replicate the genome, thereby producing more virion and releasing it outside the cell to mediate the virus's spread. This paper reviews the morphological characteristics, genome structure, encoded proteins, and function of HEV virus-like particles in order to provide a theoretical basis for basic research and comprehensive disease prevention and control.

Chloroplast genome resolution and phylogenetic analysis of Ardisia crispa var. amplifolia and Ardisia crispa var. dielsii / 药学学报

italic>Ardisia crispa (Thunb.) A. DC. is a traditional Miao medicinal herb with significant therapeutic effects in the treatment of sore throat, tonsillitis, edema of nephritis and bruising and rheumatism, etc. Ardisia crispa var. amplifolia and Ardisia crispa var. dielsii are varieties of A. crispa. A. crispa var. amplifolia and A. crispa var. dielsii are controversial in terms of species evolutionary relationships and taxonomic identification. In this study, we sequenced the whole genome sequences of A. crispa var. amplifolia and A. crispa var. dielsii chloroplasts using Illumina platform, assembled, annotated and characterized them, compared the structural features and degree of variation among chloroplast genomes using bioinformatics methods, and also downloaded constructing phylogenetic trees to analyze the phylogenetic relationships of chloroplasts in Primulaceae and Myrsinaceae using whole genome sequence information. The results showed that the complete chloroplast genome sequences of A. crispa var. amplifolia and A. crispa var. dielsii were 156 749 bp and 156 748 bp in length, with 132 genes annotated, including 87 protein-coding genes; the codon preference of A/U was greater than that of G/C; The differences in the coding regions of rps15 and rpoB genes in the comparative genome analysis can be used as loci for molecular identification of the two species; the differences in the coding regions of ycf1, ycf2, rpoC1, ycf3, petD and rpl16 genes in the chloroplast genome compared with those of the same genus can be used as loci for identification of the genus. In the phylogenetic results, A. crispa var. amplifolia and A. crispa var. dielsii were clustered together with 100% support, indicating that they are closely related. In this research, we analyzed the chloroplast genome structure and phylogenetic relationships of A. crispa var. amplifolia and A. crispa var. dielsii, providing an important theoretical basis for their molecular identification, genetic variation, breeding and phylogenetic analysis.

Mitochondrial genome sequence characteristics and phylogenetic analysis of Schizothorax argentatus / 生物工程学报

Schizothorax argentatus that only distributes in the Ili River basin in Xinjiang is one of the rare and endangered species of schizothorax in China, thus has high scientific and economic values. In this study, the complete mitochondrial genome sequence of S. argenteus with a length of 16 580 bp was obtained by high-throughput sequencing. The gene compositions and arrangement were similar to those of typical vertebrates. It contained 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a non-coding region (D-loop). The nucleotide compositions were A (30.25%), G (17.28%), C (27.20%), and T (25.27%), respectively, showing obvious AT bias and anti-G bias. Among the tRNA genes, only tRNA-Ser(GCU) could not form a typical cloverleaf structure due to the lack of dihydrouracil arm. The AT-skew and GC-skew values of the ND6 gene were fluctuating the most, suggesting that the gene may experience different selection and mutation pressures from other genes. The mitochondrial control region of S. argenteus contained three different domains, i.e., termination sequence region (ETAS), central conserved region (CSB-F, CSB-E, CSB-D, and CSB-B), and conserved sequence region (CSB1, CSB2, and CSB3). The conserved sequence fragment TT (AT) nGTG, which was ubiquitous in Cypriniformes, was identified at about 50 bp downstream CSB3. Phylogenetic relationships based on the complete mitochondrial genome sequence of 28 Schizothorax species showed that S. argenteus had differentiated earlier and had a distant relationship with other species, which may be closely related to the geographical location and the hydrological environment where it lives.

Analysis of the chloroplast genome of Incarvillea younghusbandii Sprague / 生物工程学报

Incarvillea younghusbandii Sprague is a traditional tonic herb. The roots are used as herbal medicine for nourishing and strengthening, as well as treating postpartum milk deficiency and weakness. In this study, the chloroplast genome of I. younghusbandii was sequenced and assembled by the high-throughput sequencing technology. The sequence characteristics, sequence repeats, codon usage bias, phylogenetic relationships and estimated divergence time of I. younghusbandii were analyzed. The 159 323 bp sequence contained a large single copy (80 197 bp), a small single copy (9 030 bp) and two inverted repeat sequences (35 048 bp). It contained 120 genes, including 77 protein coding genes, 8 ribosomal RNA genes and 35 transfer RNA genes. AAA was the most frequent codon in the chloroplast coding sequence of I. younghusbandii. A total of 42 simple sequence repeats were identified in the chloroplast genome. Phylogenetic analysis revealed I. younghusbandii was mostly like its taxonomically close relative Incarvillea compacta. The divergence between I. younghusbandii and I. compacta was dated to 4.66 million years ago. This study was significant for the scientific conservation and development of resources related to I. compacta. It also provides a basic genetic resource for the subsequent species identification of the genus Incarvillea, and the population genetic diversity study of Bignoniaceae.

Characteristics and phylogenetic analysis of chloroplast genome of a new type of fruit Rubus rosaefolius / 生物工程学报

The genomic DNA of Rubus rosaefolius was extracted and sequenced by Illumina NovaSeq platform to obtain the complete chloroplast genome sequence, and the sequence characteristics and phylogenetic analysis of chloroplast genes were carried out. The results showed that the complete chloroplast genome of the R. rosaefolius was 155 650 bp in length and had a typical tetrad structure, including two reverse repeats (25 748 bp each), a large copy region (85 443 bp) and a small copy region (18 711 bp). A total of 131 genes were identified in the whole genome of R. rosaefolius chloroplast, including 86 protein coding genes, 37 tRNA genes and 8 rRNA genes. The GC content of the whole genome was 36.9%. The genome of R. rosaefolius chloroplast contains 47 scattered repeats and 72 simple sequence repeating (SSR) loci. The codon preference is leucine codon, and the codon at the end of A/U is preferred. Phylogenetic analysis showed that R. rosaefolius had the closest relationship with R. taiwanicola, followed by R. rubraangustifolius and R. glandulosopunctatus. The chloroplast genome characteristics and phylogenetic analysis of R. rosaefolius provide a theoretical basis for its genetic diversity research and chloroplast development and utilization.

Characteristics of the chloroplast genome of Dracaena marginata and phylogenetic analysis / 生物工程学报

Dracaena marginata is a widely cultivated horticultural plant in the world, which has high ornamental and medicinal value. In this study, the whole genome of leaves from D. marginata was sequenced by Illumina HiSeq 4000 platform. The chloroplast genome were assembled for functional annotation, sequence characteristics and phylogenetic analysis. The results showed that the chloroplast genome of D. marginata composed of four regions with a size of 154 926 bp, which was the smallest chloroplast genome reported for Dracaena species to date. A total of 132 genes were identified, including 86 coding genes, 38 tRNA genes and 8 rRNA genes. Codon bias analysis found that the codon usage bias was weak and there was a bias for using A/U base endings. 46 simple sequence repeat and 54 repeats loci were detected in the chloroplast genome, with the maximum detection rate in the large single copy region and inverted repeat region, respectively. The inverted repeats boundaries of D. marginata and Dracaena were highly conserved, whereas gene location differences occurred. Phylogenetic analysis revealed that D. serrulata and D. cinnabari form a monophyletic clade, which was the closest relationship and conformed to the morphological classification characteristics. The analysis of the chloroplast genome of D. marginata provides important data basis for species identification, genetic diversity and chloroplast genome engineering of Dracaena.

Chloroplast genomic characterization and phylogenetic analysis of Pellionia scabra / 生物工程学报

Pellionia scabra belongs to the genus Pellionia in the family of Urticaceae, and is a high-quality wild vegetables with high nutritional value. In this study, high-throughput techniques were used to sequence, assemble and annotate the chloroplast genome. We also analyzed its structure, and construct the phylogenetic trees from the P. scabra to further study the chloroplast genome characteristics. The results showed that the chloroplast genome size was 153 220 bp, and the GC content was 36.4%, which belonged to the typical tetrad structure in P. scabra. The chloroplast genome encodes 130 genes, including 85 protein-coding genes, 37 tRNA genes, and 8 rRNA genes in P. scabra. Among them, 15 genes contained 1 intron, 2 genes contained 2 introns, and rps12 had trans-splicing, respectively. In P. scabra, chloroplast genomes could be divided into four categories, including 43 photosynthesis, 64 self-replication, other 7 coding proteins, and 4 unknown functions. A total of 51 073 codons were detected in the chloroplast genome, among which the codon encoding leucine (Leu) accounted for the largest proportion, and the codon preferred to use A and U bases. There were 72 simple sequence repeats (SSRs) in the chloroplast genome of P. scabra, containing 58 single nucleotides, 12 dinucleotides, 1 trinucleotide, and 1 tetranucleotide. The ycf1 gene expansion was present at the IRb/SSC boundary. The phylogenetic trees showed that P. scabra (OL800583) was most closely related to Elatostema stewardii (MZ292972), Elatostema dissectum (MK227819) and Elatostema laevissimum var. laevissimum (MN189961). Taken together, our results provide worthwhile information for understanding the identification, genetic evolution, and genomics research of P. scabra species.