Salmonella is a gram-negative rod-shape bacterium from the family of Enterobacteriaceae that can cause a wide range of human disease such as enteric fever, gastroenteritis and bacteremia. Here we sequenced two genomes of Salmonella bacteria isolated from the Gallus gallus domesticus host. Genomic DNA of the two Salmonella isolates were extracted and subjected to whole genome sequencing using Illumina platform. The draft genome size of the two Salmonella isolates was determined to be 4,902,295 bp (S18) and 4,847,310 bp (S20) respectively. The percentage of GC content for both draft genomes is the same which is 52.1%. Both the whole genome shotgun project (S18 and S20) has been deposited in National Center for Biotechnology Information Sequence Read Archive under the accession number of SRR7503041 (S18) and SRR7503040 (S20). The sequenced genome (S18 and S20) were aligned with the reference genome and three other Salmonella genomes from serogroup B, D and E. The data obtained show the presence of unique DNA sequences in S18 and S20 genomes. This unique DNA sequences are from the fimbrial gene group.
Next generation DNA sequencing and analysis of amplicons spanning the pharmacogene CYP2D6 suggested that the Nextera transposase used for fragmenting and providing sequencing priming sites displayed a targeting bias. This manifested as dramatically lower sequencing coverage at sites in the amplicon that appeared likely to form G-quadruplex structures. Since secondary DNA structures such as G-quadruplexes are abundant in the human genome, and are known to interact with many other proteins, we further investigated these sites of low coverage. Our investigation revealed that G-quadruplex structures are formed in vitro within the CYP2D6 pharmacogene at these sites, and G-quadruplexes can interact with the hyperactive Tn5 transposase (EZ-Tn5) with high affinity. These findings indicate that secondary DNA structures such as G-quadruplexes may represent preferential transposon integration sites and provide additional evidence for the role of G-quadruplex structures in transposition or viral integration processes.
Understanding dietary diversity is a fundamental task in the study of stump-tailed macaque, Macaca arctoides in its natural habitat. However, direct feeding observation and morphological identification using fecal samples are not effective and nearly impossible to obtain in natural habitats because this species is sensitive to human presence. As ecological methods are challenging and time-consuming, DNA metabarcoding offers a more powerful assessment of the diet. We used a chloroplast tRNL DNA metabarcoding approach to identify the diversity of plants consumed by free-ranging M. arctoides in the Malaysia-Thailand border region located in Perlis State Park, Peninsular Malaysia. DNA was extracted from three fecal samples, and chloroplast tRNL DNA was amplified and sequenced using the Illumina MiniSeq platform. Sequences were analyzed using the CLC Genomic Workbench software. A total of 145 plant species from 46 families were successfully identified as being consumed by M. arctoides. The most abundant species were yellow saraca, Saraca thaipingensis (11.70%), common fig, Ficus carica (9.33%), aramata, Clathrotropis brachypetala (5.90%), sea fig, Ficus superba (5.44%), and envireira, Malmea dielsiana (1.70%). However, Clathrotropis and Malmea are not considered Malaysian trees because of limited data available from Malaysian plant DNA. Our study is the first to identify plant taxa up to the species level consumed by stump-tailed macaques based on a DNA metabarcoding approach. This result provides an important understanding on diet of wild M. arctoides that only reside in Perlis State Park, Malaysia.
The Japanese or Honshū wolf was one the most distinct gray wolf subspecies due to its small stature and endemicity to the islands of Honshū, Shikoku, and Kyūshū. Long revered as a guardian of farmers and travellers, it was persecuted from the 17th century following a rabies epidemic, which led to its extinction in the early 20th century. To better understand its evolutionary history, we sequenced the nuclear genome of a 19th century Honshū wolf specimen to an average depth of coverage of 3.7✕. We find Honshū wolves were closely related to a lineage of Siberian wolves that were previously believed to have gone extinct in the Late Pleistocene, thereby extending the survival of this ancient lineage until the early 20th century. We also detected significant gene flow between Japanese dogs and the Honshū wolf, corroborating previous reports on Honshū wolf dog interbreeding.
Corvus macrorhynchos formerly referred to as the jungle crow or the large-billed crow is a polytypic species with unresolved taxonomy, comprising various subspecies widespread across South, Southeast, and East Asia. In this study, we report the complete mitogenome of one of these subspecies, Corvus macrorhynchos intermedius (Himalaya crow), from Pakistan. The mitochondrial genome is circular, 16,927 bp and contains typical animal mitochondrial genes (13 protein-coding genes, 2 ribosomal RNA, and 22 transfer RNA) and one non-coding region (D-loop) with a nucleotide content of A (30.6%), T (24.8%), G (14.8%), and C (29.8%). Phylogenetic analysis using the whole mitochondrial genome showed that C. m. intermedius and only reported subspecies Corvus macrorhynchos culminatus (Indian Jungle crow) are genetically distinct and it supports the recognition of the latter as a separate biospecies.
Syzygium malaccense is native to Malaysia. It is sometimes called the malay apple, malay rose-apple, mountain rose-apple, mountain apple, water apple, or French cashew. The tree is very popular in many tropical and subtropical regions for its fruit and traditional medicine. The first complete chloroplast genome of Syzygium malaccense has been reported in this study. The complete chloroplast genome of Syzygium malaccense is 158,954 bp, composed of four regions: a large single-copy region with a size of 87,991 bp, a small single copy region with a size of 18,793 bp, and two inverted repeat regions with a size of 26,085 bp. The GC content is 36.97%. A total of 132 genes were annotated, including 84 encoding proteins, eight encoding rRNA genes, 37 encoding tRNA genes, and three encoding pseudo genes. Phylogenetic analysis showed that Syzygium aromaticum, Syzygium cumini, and Syzygium forrestii are closely related to Syzygium malaccense.
The increasing interest in understanding the evolutionary relationship between members of the Pteropodidae family has been greatly aided by genomic data from the Old World fruit bats. Here we present the complete mitogenome of Geoffroy's rousette, Rousettus amplexicaudatus found in Peninsular Malaysia . The mitogenome constructed is 16,511bp in length containing 37 genes; 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and a D-loop region. The overall base composition is estimated to be 32.28% for A, 25.64% for T, 14.09% for G and 27.98% for C, indicating a slightly AT rich feature (57.93%). A phylogenetic and BLASTn analysis against other available mitogenomes showed Malaysian R. amplexicaudatus matched 98% similarity to the same species in Cambodia and Vietnam. However, it differed considerably (92.53% similarity) with the same species in the Philippines. This suggests flexibility in Rousettus sp. with regards to adapting to mesic and dry habitats, ability for long-distance dispersal and remarkably precise lingual echolocation thus supporting its wide-range distribution and colonization. Further taxonomical and mitogenomic comparatives are required in resolving the evolutionary relationship between Rousettus spp.
The cavity-nesting honeybee Apis nuluensis inhabits only the highlands of Mount Kinabalu of Sabah, Borneo Island. The mitochondrial genome is a circular molecule of approximately 1.6 kb that includes 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and one AT-rich control region. The average AT content was 84.5%. The start codons ATC, ATG, and ATT were found in one, three, and nine genes, respectively, whereas the stop codon TAA was observed in all genes. The phylogenetic relationship, inferred using 13 PCGs, was consistent with that reported in previous studies that predicted a sister taxon relationship between A. nuluensis and A. cerana.
Oil palm (Elaeis guineensis Jacq.) is the most traded crop among the economically important palm species. Here, we report an extended version genome of E. guineensis that is 1.2 Gb in length, an improvement of the physical genome coverage to 79% from the previous 43%. The improvement was made by assigning an additional 1968 originally unplaced scaffolds that were available publicly into the physical genome. By integrating three ultra-dense linkage maps and using them to place genomic scaffolds, the 16 pseudomolecules were extended. As we show, the improved genome has enhanced the mapping resolution for genome-wide association studies (GWAS) and permitted further identification of candidate genes/protein-coding regions (CDSs) and any non-coding RNA that may be associated with them for further studies. We then employed the new physical map in a comparative genomics study against two other agriculturally and economically important palm species-date palm (Phoenix dactylifera L.) and coconut palm (Cocos nucifera L.)-confirming the high level of conserved synteny among these palm species. We also used the improved oil palm genome assembly version as a palm genome reference to extend the date palm physical map. The improved genome of oil palm will enable molecular breeding approaches to expedite crop improvement, especially in the largest subfamily of Arecoideae, which consists of 107 species belonging to Arecaceae.
Vatica mangachapoi is a tree up to 20 m tall with white resinous. It is distributed in China (Hainan province), Indonesia, Malaysia (N Borneo), Philippines, Thailand, and Vietnam. It grows in forests on hills and mountain slopes below 700 metres. Its durable wood is used for making boats and building bridges and houses. It has been ranked as a VU (Vulnerable) species in China. Here we report and characterize the complete plastid genome sequence of V. mangachapoi in an effort to provide genomic resources useful for promoting its conservation and phylogenetic research. The complete plastome is 151,538 bp in length and contains the typical structure and gene content of angiosperm plastome, including two Inverted Repeat (IR) regions of 23,921 bp, a Large Single-Copy (LSC) region of 83,587 bp and a Small Single-Copy (SSC) region of 20,109 bp. The plastome contains 114 genes, consisting of 80 unique protein-coding genes, 30 unique tRNA gene, and 4 unique rRNA genes. The overall A/T content in the plastome of V. mangachapoi is 62.80%. The phylogenetic analysis indicated that V. mangachapoi and V. odorata is closely related and as an independent branch in Malvales in our study. The complete plastome sequence of V. mangachapoi will provide a useful resource for the conservation genetics of this species and for the phylogenetic studies for Vatica.
We have completely sequenced the genomes of two Nipah virus (NiV) isolates, one from the throat secretion and the other from the cerebrospinal fluid (CSF) of the sole surviving encephalitic patient with positive CSF virus isolation in Malaysia. The two genomes have 18246 nucleotides each and differ by only 4 nucleotides. The NiV genome is 12 nucleotides longer than the Hendra virus (HeV) genome and both genomes have identical leader and trailer sequence lengths and hexamer-phasing positions for all their genes. Both NiV and HeV are also very closely related with respect to their genomic end sequences, gene start and stop signals, P gene-editing signals and deduced amino acid sequences of nucleocapsid protein, phosphoprotein, matrix protein, fusion protein, glycoprotein and RNA polymerase. The existing evidence demonstrates a clear need for the creation of a new genus within the subfamily Paramyxovirinae to accommodate the close similarities between NiV and HeV and their significant differences from other members of the subfamily.
The higher-level taxonomy of the stingrays (Dasyatidae) has never been comprehensively reviewed. Recent phylogenetic studies, supported by morphological data, have provided evidence that the group is monophyletic and consists of four major subgroups, the subfamilies Dasyatinae, Neotrygoninae, Urogymninae and Hypolophinae. A morphologically based review of 89 currently recognised species, undertaken for a guide to the world's rays, indicated that most of the currently recognised dasyatid genera are not monophyletic groups. These findings were supported by molecular analyses using the NADH2 gene for about 77 of these species, and this topology is supported by preliminary analyses base on whole mitochondrial genome comparisons. These molecular analyses, based on data generated from the Chondrichthyan Tree of Life project, are the most taxon-rich data available for this family. Material from all of the presently recognised genera (Dasyatis, Pteroplatytrygon and Taeniurops [Dasyatinae]; Neotrygon and Taeniura [Neotrygoninae]; Himantura and Urogymnus [Urogymninae]; and Makararaja and Pastinachus [Hypolophinae]), are included and their validity largely supported. Urogymnus and the two most species rich genera, Dasyatis and Himantura, are not considered to be monophyletic and were redefined based on external morphology. Seven new genus-level taxa are erected (Megatrygon and Telatrygon [Dasyatinae]; Brevitrygon, Fluvitrygon, Fontitrygon, Maculabatis and Pateobatis [Urogymninae], and an additional three (Bathytoshia, Hemitrygon and Hypanus [Dasyatinae]) are resurrected from the synonymy of Dasyatis. The monotypic genus Megatrygon clustered with 'amphi-American Himantura' outside the Dasyatidae, and instead as the sister group of the Potamotrygonidae and Urotrygonidae. Megatrygon is provisionally retained in the Dasyatinae pending further investigation of its internal anatomy. The morphologically divergent groups, Bathytoshia and Pteroplatytrygon, possibly form a single monophyletic group so further investigation is needed to confirm the validity of Pteroplatytrygon. A reclassification of the family Dasyatidae is provided and the above taxa are defined based on new morphological data.
Agricultural development in the tropics lags behind development in the
temperate latitudes due to the lack of advanced technology, and various biotic and abiotic
factors. To cope with the increasing demand for food and other plant-based products,
improved crop varieties have to be developed. To breed improved varieties, a better
understanding of crop genetics is necessary. With the advent of next-generation DNA
sequencing technologies, many important crop genomes have been sequenced. Primary
importance has been given to food crops, including cereals, tuber crops, vegetables, and
fruits. The DNA sequence information is extremely valuable for identifying key genes
controlling important agronomic traits and for identifying genetic variability among the
cultivars. However, massive DNA re-sequencing and gene expression studies have to be
performed to substantially improve our understanding of crop genetics. Application of the
knowledge obtained from the genomes, transcriptomes, expression studies, and
epigenetic studies would enable the development of improved varieties and may lead to a
second green revolution. The applications of next generation DNA sequencing
technologies in crop improvement, its limitations, future prospects, and the features of
important crop genome projects are reviewed herein.
(GTG)5 PCR is a type of repetitive extragenic palindromic (rep)-PCR which amplifies the (GTG)5 repetitive element that lays throughout the bacterial genome. In this study, fifty, thirty-nine and forty-nine unknown bacteria were isolated from aquaculture farms in Miri, Limbang and Lundu, respectively. (GTG)5 PCR was used to screen for clonal diversity among the isolates according to sampling sites. Banding profiles obtained from electrophoresed (GTG)5 PCR products were analyzed by RAPDistance Software to generate a dendrogram of neighbor joining tree (NJT) format. Based on the constructed dendrogram, representative isolates were selected for further identification. Conserved 16S rRNA region of the selected bacteria isolates were amplified and purified DNA products were sequenced. (GTG)5 PCR is useful in differentiation of unknown bacterial isolates and 16S rRNA analysis species identity of the bacteria in Sarawak aquaculture environment. The high diversity of bacteria in aquaculture environment may be caused by contamination from various sources.
The human genome contains many submicroscopic copy number variations which includes deletions, duplications and insertions. Although conventional karyotyping remains an important diagnostic tool in evaluating a dysmorphic patient with mental retardation, molecular diagnostic technology such as array comparative genomic hybridization (aCGH) has proven to be sensitive and reliable in detecting these submicroscopic anomalies. A 3 month-old infant with dysmorphic facies, microcephaly and global developmental delay was referred for genetic evaluation. Preliminary karyotyping which was confounded by the quality of metaphase spread was normal; however, aCGH detected a 30.6Mb deletion from 5p15.33-p13.3. This case illustrates the usefulness of aCGH as an adjunctive investigative tool for detecting chromosomal imbalances.
The role of mitochondria in tumorigenesis has regained much attention as it could dysregulate cellular energetics, oxidative stress and apoptosis. However, the role of mitochondria in different grade gliomasis still unknown. This study aimed to identify mitochondrial DNA (mtDNA) sequence variations that could possibly affect the mitochondrial functions and also the oxidative stress status. Three different grades of human glioma cell lines and a normal human astrocyte cell line were cultured in-vitro and tested for oxidative stress biomarkers. Relative oxidative stress level, mitochondria activity, and mitochondrial mass were determined by live cell imaging with confocal laser scanning microscope using CM-H2DCFDA, MitoTracker Green, and MitoTracker Orange stains. The entire mitochondrial genome was sequenced using the AffymetrixGeneChip Human Mitochondrial Resequencing Array 2.0. The mitochondrial sequence variations were subjected to phylogenetic haplogroup assessment and pathogenicity of the mutations were predicted using pMUT and PolyPhen2. The Grade II astrocytoma cells showed increased oxidative stress wherea high level of 8-OHdG and oxidative stress indicator were observed. Simultaneously, Grade II and III glioma cells showed relatively poor mitochondria functions and increased number of mutations in the coding region of the mtDNA which could be due to high levels of oxidative stress in these cells. These non-synonymous mtDNA sequence variations were predicted to be pathogenic and could possibly lead to protein dysfunction, leading to oxidative phosphorylation (OXPHOS) impairment, mitochondria dysfunction and could create a vicious cycle of oxidative stress. The Grade IV cells had no missense mutation but preserved intact mitochondria and excellent antioxidant defense mechanisms thus ensuring better survival. In conclusion, Grade II and III glioma cells demonstrated coding region mtDNA mutations, leading to mitochondrial dysfunction and higher oxidative stress.
The Asian tiger mosquito, Aedes albopictus, is an invasive vector mosquito of substantial public health concern. The large genome size (~1.19-1.28 Gb by cytofluorometric estimates), comprised of ~68% repetitive DNA sequences, has made it difficult to produce a high-quality genome assembly for this species. We constructed a high-density linkage map for Ae. albopictus based on 111,328 informative SNPs obtained by RNAseq. We then performed a linkage-map anchored reassembly of AalbF2, the genome assembly produced by Palatini et al. (2020). Our reassembled genome sequence, AalbF3, represents several improvements relative to AalbF2. First, the size of the AalbF3 assembly is 1.45 Gb, almost half the size of AalbF2. Furthermore, relative to AalbF2, AalbF3 contains a higher proportion of complete and single-copy BUSCO genes (84.3%) and a higher proportion of aligned RNAseq reads that map concordantly to a single location of the genome (46%). We demonstrate the utility of AalbF3 by using it as a reference for a bulk-segregant-based comparative genomics analysis that identifies chromosomal regions with clusters of candidate SNPs putatively associated with photoperiodic diapause, a crucial ecological adaptation underpinning the rapid range expansion and climatic adaptation of A. albopictus.
Introduction. Tigecycline is currently acknowledged to be one of the most effective antibiotics against infections caused by Mycobacteroides abscessus.Gap statement. The genetic determinants of tigecycline resistance in M. abscessus are not well understood.Aim. In this study, we characterized a tigecycline-resistant M. abscessus mutant, designated CL7, to identify the potential resistance mechanism.Methodology. CL7 was characterized using antimicrobial susceptibility testing, whole-genome sequencing, PCR and RT-qPCR. For biological verification, gene overexpression assays were carried out.Results. Whole-genome sequencing and the subsequent gene overexpression assays showed that CL7 harboured a stop-gain mutation in MAB_3543 c, which may be responsible for the tigecycline resistance phenotype. This gene encodes an orthologue of SigH, which is involved in the positive regulation of physiological stress response and is negatively regulated by the RshA anti-sigma factor in Mycobacterium tuberculosis. We hypothesized that the MAB_3543 c mutation may disrupt the interaction between SigH and RshA (MAB_3542 c). RT-qPCR analyses revealed the upregulation of MAB_3543 c and other key stress response genes, which has previously been shown to be a hallmark of SigH-RshA bond disruption and tigecycline resistance.Conclusion. The MAB_3543c mutation may represent a novel determinant of tigecycline resistance in M. abscessus. The findings of this study will hopefully contribute to our knowledge of potential tigecycline resistance mechanisms in M. abscessus, which may lead to better diagnostics and treatment modalities in the future.
Tapinoma indicum (Forel) (Hymenoptera: Formicidae) is a nuisance pest in Asia countries. However, studies on T. indicum are limited, especially in the field of molecular biology, to investigate the species characteristic at the molecular level. This paper aims to provide valuable genetic markers as tools with which to study the T. indicum population. In this study, a total of 143,998 microsatellite markers were developed based on the 2.61 × 106 microsatellites isolated from T. indicum genomic DNA sequences. Fifty selected microsatellite markers were amplified with varying numbers of alleles ranging from 0 to 19. Seven out of fifty microsatellite markers were characterized for polymorphism with the Hardy-Weinberg equilibrium (HWE) and linkage disequilibrium (LD) analysis. All seven microsatellite markers demonstrated a high polymorphic information content (PIC) value ranging from 0.87 to 0.93, with a mean value of 0.90. There is no evidence of scoring errors caused by stutter peaks, no large allele dropout, and no linkage disequilibrium among the seven loci; although loci Ti-Tr04, Ti-Tr09, Ti-Te04, Ti-Te13, and Ti-Pe5 showed signs of null alleles and deviation from the HWE due to excessive homozygosity. In conclusion, a significant amount of microsatellite markers was developed from the data set of next-generation sequencing, and seven of microsatellite markers were validated as informative genetic markers that can be utilized to study the T. indicum population.