The complete chloroplast genome of Callicarpa macrophylla Vahl.

Callicarpa macrophylla Vahl. belongs to the family Lamiaceae. Its root is a widely used Yao Medicine (YM) to treat internal and external bleeding at the Yao minority areas in southern China. Here, we provide the complete chloroplast genome of C. macrophylla which was collected from Laibin city in Guangxi, China. The total length of the chloroplast genome is 154,141 bp, including a large single-copy (LSC) region, a small single-copy (SSC) region, and a pair of inverted repeats (IRs) regions which are separated by the LSC and SSC, with lengths of 84,904 bp, 17,839 bp, and 25,699 bp, respectively. One hundred and thirty-one genes were identified, including 89 protein-coding genes, 34 tRNA genes, and eight rRNA genes. The overall GC content is 38%. Phylogenetic analysis revealed that C. macrophylla is closely related to C. integerrima var. chinensis.

Full-Length Genome of an Ogataea polymorpha Strain CBS4732 ura3Δ Reveals Large Duplicated Segments in Subtelomeric Regions.

Background: Currently, methylotrophic yeasts (e.g., Pichia pastoris, Ogataea polymorpha, and Candida boindii) are subjects of intense genomics studies in basic research and industrial applications. In the genus Ogataea, most research is focused on three basic O. polymorpha strains-CBS4732, NCYC495, and DL-1. However, the relationship between CBS4732, NCYC495, and DL-1 remains unclear, as the genomic differences between them have not be exactly determined without their high-quality complete genomes. As a nutritionally deficient mutant derived from CBS4732, the O. polymorpha strain CBS4732 ura3Δ (named HU-11) is being used for high-yield production of several important proteins or peptides. HU-11 has the same reference genome as CBS4732 (noted as HU-11/CBS4732), because the only genomic difference between them is a 5-bp insertion. Results: In the present study, we have assembled the full-length genome of O. polymorpha HU-11/CBS4732 using high-depth PacBio and Illumina data. Long terminal repeat retrotransposons (LTR-rts), rDNA, 5' and 3' telomeric, subtelomeric, low complexity and other repeat regions were exactly determined to improve the genome quality. In brief, the main findings include complete rDNAs, complete LTR-rts, three large duplicated segments in subtelomeric regions and three structural variations between the HU-11/CBS4732 and NCYC495 genomes. These findings are very important for the assembly of full-length genomes of yeast and the correction of assembly errors in the published genomes of Ogataea spp. HU-11/CBS4732 is so phylogenetically close to NCYC495 that the syntenic regions cover nearly 100% of their genomes. Moreover, HU-11/CBS4732 and NCYC495 share a nucleotide identity of 99.5% through their whole genomes. CBS4732 and NCYC495 can be regarded as the same strain in basic research and industrial applications. Conclusion: The present study preliminarily revealed the relationship between CBS4732, NCYC495, and DL-1. Our findings provide new opportunities for in-depth understanding of genome evolution in methylotrophic yeasts and lay the foundations for the industrial applications of O. polymorpha CBS4732, NCYC495, DL-1, and their derivative strains. The full-length genome of O. polymorpha HU-11/CBS4732 should be included into the NCBI RefSeq database for future studies of Ogataea spp.

Comparative Multi-Omics of Tender Shoots from a Novel Evergrowing Tea Cultivar Provide Insight into the Winter Adaptation Mechanism.

Tea (Camellia sinensis [L.] O. Kuntze) tree is a perennial plant in which winter dormancy is an important biological adaptation to environmental changes. We discovered and reported a novel tea tree cultivar that can generate tender shoots in winter several years ago, but the molecular mechanism for this unique phenotype remains unknown . Here, we conducted comparative transcriptomics, proteomics and metabolomics along with phytohormone quantitation between the winter and spring tender shoots to investigate the physiological basis and putative regulatory mechanisms of its evergrowing character during winter. Our multi-omics study has led to the following findings. Gibberellin (GA) levels and key enzymes for GA biosynthesis and the signal transduction pathway were increased in the winter shoots, causing the ABA/GA content ratio to decrease, which might play a key regulatory role in maintaining normal growth during winter. The abundance of proteins, genes and metabolites involved in energy metabolism was all increased in winter shoots, indicating that energy is critical for continuous growth under the relatively weak-light and low-temperature environment. Abiotic resistance-related proteins and free amino acids were also increased in abundance in the winter shoots, which possibly represents an adaptation response to winter conditions. These results allowed us to hypothesize a novel molecular mechanism of adaptation for this unique tender shoot evergrowing in winter.

Full-length genome sequence of segmented RNA virus from ticks was obtained using small RNA sequencing data.

BACKGROUND: In 2014, a novel tick-borne virus of the Flaviviridae family was first reported in the Mogiana region of Brazil and named the Mogiana tick virus (MGTV). Thereafter, the Jingmen tick virus (JMTV), Kindia tick virus (KITV), and Guangxi tick virus (GXTV)-evolutionarily related to MGTV-were reported. RESULTS: In the present study, we used small RNA sequencing (sRNA-seq) to detect viruses in ticks and discovered a new MGTV strain in Amblyomma testudinarium ticks collected in China's Yunnan Province in 2016. We obtained the full-length genome sequence of this MGTV strain Yunnan2016 (GenBank: MT080097, MT080098, MT080099 and MT080100) and recommended it for its inclusion in the NCBI RefSeq database for future studies on MGTV, JMTV, KITV and GXTV. Phylogenetic analysis showed that MGTV, JMTV, KITV and GXTV are monophyletic and belong to a MGTV group. Furthermore, this MGTV group of viruses may be phylogenetically related to geographical regions that were formerly part of the supercontinents Gondwana and Laurasia. CONCLUSIONS: To the best of our knowledge, this is the first study in which 5' and 3' sRNAs were used to generate full-length genome sequences of, but not limited to, RNA viruses. We also demonstrated the feasibility of using the sRNA-seq based method for the detection of viruses in pooled two and even possible one small ticks. MGTV may preserve the characteristic of ancient RNA viruses, which can be used to study the origin and evolution of RNA viruses. In addition, MGTV can be used as novel species for studies in phylogeography.

A Phenotypic Characterization of Two Isolates of a Multidrug-Resistant Outbreak Strain of Mycobacterium tuberculosis with Opposite Epidemiological Fitness.

Tuberculosis (TB) is an infectious disease, caused by Mycobacterium tuberculosis, primarily affecting the lungs. The M. tuberculosis strain of the Haarlem family named M was responsible for a large multidrug-resistant TB (MDR-TB) outbreak in Buenos Aires. This outbreak started in the early 1990s and in the mid 2000s still accounted for 29% of all MDR-TB cases in Argentina. By contrast, a clonal variant of strain M, named 410, has caused a single tuberculosis case since the onset of the outbreak. The molecular bases of the high epidemiological fitness of the M strain remain unclear. To assess its unique molecular properties, herein, we performed a comparative protein and lipid analysis of a representative clone of the M strain (Mp) and the nonprosperous M variant 410. We also evaluated their growth in low pH. The variant 410 had higher levels of latency proteins under standard conditions and delayed growth at low pH, suggesting that it is more sensitive to stress stimuli than Mp. Moreover, Mp showed higher levels of mycolic acids covalently attached to the cell wall and lower accumulation of free mycolic acids in the outer layer than the 410 strain. The low expression of latency proteins together with the reduced content of surface mycolic acids may facilitate Mp to evade the host immune responses.

Mesorhizobium alexandrii sp. nov., isolated from phycosphere microbiota of PSTs-producing marine dinoflagellate Alexandrium minutum amtk4.

An aerobic, Gram-stain-negative, motile and rod-shaped bacterial strain, designated as Z1-4T, was isolated from the phycosphere microbiota of marine dinoflagellate Alexandrium minutum that produces paralytic shellfish poisoning toxins. Phylogenetic analysis based on 16S rRNA gene sequences showed that the new isolate belongs to the genus Mesorhizobium, and it was closely related to Mesorhizobium waimense LMG 28228T and Mesorhizobium amorphae LMG 18977T with both 16S rRNA gene sequence similarities of 97.3%. The values of average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) relatedness between strain Z1-4T and its relatives are both well below the thresholds used for the delineation of a new species. A genome-based phylogenetic tree constructed by up-to-date bacterial core gene set (UBCG) indicates that strain Z1-4T forms an independent branch within the genus Mesorhizobium. The respiratory quinone of strain Z1-4T was Q-10. The major fatty acids were similar to other members of the genus Mesorhizobium containing the summed feature 8, C16:0, C19:0cycloω8c, C17:0 and summed feature 3. The polar lipids are phosphatidylmonomethylethanolamine, diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, an unidentified aminophospholipid, five glycolipids and seven unknown polar lipids. The DNA G + C content was determined to be 62.1 mol % based on its genomic sequence. Combined evidences based on the genotypic, chemotaxonomic and phenotypic characteristics clearly indicates that strain Z1-4T represents a novel species of the genus Mesorhizobium, for which the name Mesorhizobium alexandrii sp. nov. is proposed. The type strain is Z1-4T (= KCTC 72512T = CCTCC AB 2019101T).

Correction for Yu et al., "Draft Genome Sequence of Lactobacillus reuteri Strain LR CGMCC 11154, Isolated from the Feces of Healthy Weaned Piglets".

[This corrects the article DOI: 10.1128/MRA.01552-18.].

Draft Genome Sequence of Lactobacillus reuteri Strain LR CGMCC 11154, Isolated from the Feces of Healthy Weaned Piglets.

Lactobacillus reuteri strain LR CGMCC 11154, which was isolated from the feces of healthy weaned piglets, was experimentally proven to be a probiotic bacterium. The whole genome was sequenced on the Illumina Miseq platform to obtain the draft genome, which consists of 120 contigs totaling 1.9 Mbp encoding 1,854 genes.

Quantification of enterohemorrhagic Escherichia coli O157:H7 protein abundance by high-throughput proteome.

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is a human pathogen responsible for diarrhea, hemorrhagic colitis and hemolytic uremic syndrome (HUS). To promote a comprehensive insight into the molecular basis of EHEC O157:H7 physiology and pathogenesis, the combined proteome of EHEC O157:H7 strains, Clade 8 and Clade 6 isolated from cattle in Argentina, and the standard EDL933 (clade 3) strain has been analyzed. From shotgun proteomic analysis a total of 2,644 non-redundant proteins of EHEC O157:H7 were identified, which correspond approximately 47% of the predicted proteome of this pathogen. Normalized spectrum abundance factor analysis was performed to estimate the protein abundance. According this analysis, 50 proteins were detected as the most abundant of EHEC O157:H7 proteome. COG analysis showed that the majority of the most abundant proteins are associated with translation processes. A KEGG enrichment analysis revealed that Glycolysis / Gluconeogenesis was the most significant pathway. On the other hand, the less abundant detected proteins are those related to DNA processes, cell respiration and prophage. Among the proteins that composed the Type III Secretion System, the most abundant protein was EspA. Altogether, the results show a subset of important proteins that contribute to physiology and pathogenicity of EHEC O157:H7.

Overexpressed Proteins in Hypervirulent Clade 8 and Clade 6 Strains of Escherichia coli O157:H7 Compared to E. coli O157:H7 EDL933 Clade 3 Strain.

Escherichia coli O157:H7 is responsible for severe diarrhea and hemolytic uremic syndrome (HUS), and predominantly affects children under 5 years. The major virulence traits are Shiga toxins, necessary to develop HUS and the Type III Secretion System (T3SS) through which bacteria translocate effector proteins directly into the host cell. By SNPs typing, E. coli O157:H7 was separated into nine different clades. Clade 8 and clade 6 strains were more frequently associated with severe disease and HUS. In this study, we aimed to identify differentially expressed proteins in two strains of E. coli O157:H7 (clade 8 and clade 6), obtained from cattle and compared them with the well characterized reference EDL933 strain (clade 3). Clade 8 and clade 6 strains show enhanced pathogenicity in a mouse model and virulence-related properties. Proteins were extracted and analyzed using the TMT-6plex labeling strategy associated with two dimensional liquid chromatography and mass spectrometry in tandem. We detected 2241 proteins in the cell extract and 1787 proteins in the culture supernatants. Attention was focused on the proteins related to virulence, overexpressed in clade 6 and 8 strains compared to EDL933 strain. The proteins relevant overexpressed in clade 8 strain were the curli protein CsgC, a transcriptional activator (PchE), phage proteins, Stx2, FlgM and FlgD, a dienelactone hydrolase, CheW and CheY, and the SPATE protease EspP. For clade 6 strain, a high overexpression of phage proteins was detected, mostly from Stx2 encoding phage, including Stx2, flagellin and the protease TagA, EDL933_p0016, dienelactone hydrolase, and Haemolysin A, amongst others with unknown function. Some of these proteins were analyzed by RT-qPCR to corroborate the proteomic data. Clade 6 and clade 8 strains showed enhanced transcription of 10 out of 12 genes compared to EDL933. These results may provide new insights in E. coli O157:H7 mechanisms of pathogenesis.

Structure-based fragment shuffling of two fungal phytases for combination of desirable properties.

Aspergillus niger NRRL 3135 phytase (Anp) and Aspergillus fumigatus ATCC 13073 phytase (Afp) are quite different but mutually complementary in many properties. A semi-rational protein engineering strategy based on 3D structure and sequence alignment was used to take advantage of the desirable characteristics of both enzymes. Each phytase was divided into seven fragments, including regions I-VII (I, 1-47; II, 59-133; III, 139-172; IV, 178-237; V, 246-329; VI338-381; VII, 404-444). The equivalent regions were swapped to construct an array of chimeras. Among the functional chimeras expressed in the yeast Pichia pastoris, novel phytases with combinations of the most desirable properties, including heat-resistance, were obtained. Correlations of individual regions with detailed differences were established by systematic evaluation of the substitutions. Regions II and VI contributed to the difference in specific activity at pH 5.0. Regions IV and V of Anp fully accounted for its second pH optimum at pH 2.5. Most influences of substitutions were additive, except those of regions V and VI. Exchanging both regions led to different impacts upon K(m) and activity at approximately pH 4.0 compared with the replacement of either.

[High expression of LIP1 in Pichia pastoris].

The gene of LIP1, the most important isoenzyme of Candida rugosa lipase (CRL), was artificially synthesized according to its mature peptide sequence. It consisted of 20 codons of preference in Pichia pastoris. The artificial gene was cloned into methanol-inducible expression vector pPICZalphaA, and constitutive expression vector pGAPZalphaA, respectively. The linearized recombinant plasmids were transformed into chromosome of Pichia pastoris SMD1168H strain by electroporation. The abilities of expressing LIP1 in both transformed yeasts had been compared, and the yeast transformed with pGAPZalphaA was more efficient than pPICZalphaA. A recombinant yeast strain named CHT-II expressed LIP1 constitutively, and was the most efficient one. Some enzymatic properties of the recombinant LIP1 were also determined. CHT-II secreted LIP1 into supernate at a level of 2.00x10(5) u/L after 72 h (the cells had been transferred to fresh culture medium at the 24th h). After optimizing the conditions for high cell-density fermentation, the selected yeast strain could secrete LIP1 into supernate at a level of 1.395x10(6) u/L after 72 h. The results indicated that this modification of lip1 gene was successful.