ABSTRACT
ObjectiveTo obtain high-quality chloroplast genome information on Stemona tuberosa and clarify its structure， sequence features， and phylogenetic status. MethodThe Illumina NovaSeq 6000 and PacBio RS Ⅱ platforms were used for library construction and sequencing of S. tuberosa， respectively. The data from both sequencing platforms were combined and subjected to bioinformatics analysis for genome assembly and base correction， resulting in a high-quality chloroplast genome. Subsequently， sequence features， repetitive sequences， gene diversity， and phylogeny were analyzed. ResultThe chloroplast genome size of S. tuberosa was determined to be 154 379 bp. The structure of the chloroplast genome followed the typical quadripartite circular form， consisting of a pair of inverted repeat regions （IRs） with a length of 27 074 bp， a small single-copy region （SSC） of 17 924 bp， and a large single-copy region （LSC） of 82 307 bp. The average GC content was 37.86%. A total of 121 genes were annotated， including 30 tRNA genes， four rRNA genes， and 87 protein-coding genes. Among them， six tRNA genes and 12 protein-coding genes contained introns. In the chloroplast genome of S. tuberosa， 49 long repetitive sequences and 59 single-nucleotide simple sequence repeats （SSRs） were identified. Comparative analysis of chloroplast genomes among four Stemona species revealed high diversity in the ycf1 and ndhF genes. The phylogenetic tree constructed based on the chloroplast genome showed consistent classification with the current taxonomic status of S. tuberosa. ConclusionThe high-quality chloroplast genome of S. tuberosa was successfully assembled， providing valuable information on the structure and sequence features of chloroplast genomes in four Stemona species， including S. tuberosa. These findings lay a foundation for the identification， evolution， and phylogenetic studies of medicinal plants in the genus Stemona.
ABSTRACT
BACKGROUND: Endometritis is the most common disease of dairy cows and traditionally treated with antibiotics. Lactic acid bacteria can inhibit the growth of pathogens and also have potential for treatment of endometritis. Using PacBio single-molecule real-time sequencing technology, we sequenced the fulllength l6S rRNA of the microbiota in uterine mucus samples from 31 cows with endometritis, treated with lactic acid bacteria (experimental [E] group) and antibiotics (control [C] group) separately. Microbiota profiles taken before and after treatment were compared. RESULTS: After both treatments, bacterial species richness was significantly higher than before, but there was no significant difference in bacterial diversity. Abundance of some bacteria increased after both lactic acid bacteria and antibiotic treatment: Lactobacillus helveticus, Lactococcus lactis, Lactococcus raffinolactis, Pseudomonas alcaligenes and Pseudomonas veronii. The bacterial species that significantly decreased in abundance varied depending on whether the cows had been treated with lactic acid bacteria or antibiotics. Abundance of Staphylococcus equorum and Treponema brennaborense increased after lactic acid bacteria treatment but decreased after antibiotic treatment. According to COG-based functional metagenomic predictions, 384 functional proteins were significantly differently expressed after treatment. E and C group protein expression pathways were significantly higher than before treatment (p < 0.05). CONCLUSIONS: In this study, we found that lactic acid bacteria could cure endometritis and restore a normal physiological state, while avoiding the disadvantages of antibiotic treatment, such as the reductions in abundance of beneficial microbiota. This suggests that lactic acid bacteria treatment has potential as an alternative to antibiotics in the treatment of endometritis in cattle.