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The firefly genus Oculogryphus Jeng, Engel & Yang, 2007 is a rare-species group endemic to Asia. Since its establishment, its position has been controversial but never rigorously tested. To address this perplexing issue, we are the first to present the complete mitochondrial sequence of Oculogryphus, using the material of O. chenghoiyanae Yiu & Jeng, 2018 determined through a comprehensive morphological identification. Our analyses demonstrate that its mitogenome exhibits similar characteristics to that of Stenocladius, including a rearranged gene order between trnC and trnW, and a long intergenic spacer (702 bp) between the two rearranged genes, within which six remnants (29 bp) of trnW were identified. Further, we incorporated this sequence into phylogenetic analyses of Lampyridae based on different molecular markers and datasets using ML and BI analyses. The results consistently place Oculogryphus within the same clade as Stenocladius in all topologies, and the gene rearrangement is a synapomorphy for this clade. It suggests that Oculogryphus should be classified together with Stenocladius in the subfamily Ototretinae at the moment. This study provides molecular evidence confirming the close relationship between Oculogryphus and Stenocladius and discovers a new phylogenetic marker helpful in clarifying the monophyly of Ototretinae, which also sheds a new light on firefly evolution.

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The genes encoding ribosomal RNA are highly conserved across life and in almost all eukaryotes are present in large tandem repeat arrays called the rDNA. rDNA repeat unit size is conserved across most eukaryotes but has expanded dramatically in mammals, principally through the expansion of the intergenic spacer region that separates adjacent rRNA coding regions. Here, we used long-read sequence data from representatives of the major amniote lineages to determine where in amniote evolution rDNA unit size increased. We find that amniote rDNA unit sizes fall into two narrow size classes: "normal" (∼11-20 kb) in all amniotes except monotreme, marsupial, and eutherian mammals, which have "large" (∼35-45 kb) sizes. We confirm that increases in intergenic spacer length explain much of this mammalian size increase. However, in stark contrast to the uniformity of mammalian rDNA unit size, mammalian intergenic spacers differ greatly in sequence. These results suggest a large increase in intergenic spacer size occurred in a mammalian ancestor and has been maintained despite substantial sequence changes over the course of mammalian evolution. This points to a previously unrecognized constraint on the length of the intergenic spacer, a region that was thought to be largely neutral. We finish by speculating on possible causes of this constraint.

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Hoya verticillata var verticillata, an epiphytic plant, is both an ornamental and a valuable medicinal plant. However, H. verticillata has a similar morphology to other species belonging to the Hoya genus, so it is challenging to distinguish the H. verticillata var verticillata, plant accurately. Alternatively, if H. verticillata var verticillata, is deformed or powdered, it is more challenging to identify. This dataset includes information on H. verticillata var verticillata, samples collected from the natural environment and four chloroplast DNA markers to support H. verticillata var verticillata, species identification. Phylogenetic analysis based on sequences of intergenic spacer regions (trnK-rps16, rps16-trnQ, psbI-atpA, and ndhC-trnV) shows that H. verticilata var verticillata, is very closely related and distributed in the same group as Hoya carnosa with a Bootstrap coefficient of 99-100 %. Four intergenic spacer region sequences, trnK-rps16, rps16-trnQ, psbI-atpA, and ndhC-trnV from the chloroplast genome are potential DNA barcoding candidates to distinguish H. verticilata var verticillata, from different species in the Hoya genus.

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Crude drug Angelicae acutilobae radix is one of the most important crude drugs in Japanese traditional medicine and is used mainly for the treatment of gynecological disorders. In the listing in the Japanese Pharmacopoeia XVIII, Angelicae acutilobae radix is defined as the root of Angelica acutiloba (Apiaceae), which has long been produced on an industrial scale in Japan. With the aging of farmers and depopulation of production areas, the domestic supply has recently declined and the majority of the supply is now imported from China. Due to having only slightly different morphological and chemical characteristics for the Apiaceae roots used to produce dried roots for Chinese medicines, the plant species originating the crude drug Apiaceae roots may be incorrectly identified. In particular, Angelicae sinensis radix, which is widely used in China, and Angelicae acutilobae radix are difficult to accurately identify by morphology and chemical profiles. Thus, in order to differentiate among Angelicae acutilobae radix and other radixes originated from Chinese medicinal Apiaceae plants, we established DNA markers. Using DNA sequences for the chloroplast psbA-trnH intergenic spacer and nuclear internal transcribed spacer regions, Angelicae acutilobae radix and other Chinese Apiaceae roots, including Angelicae sinensis radix, can be definitively identified.

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Whipple's disease caused by Tropheryma whipplei is difficult to diagnose because of a broad spectrum of manifestations and non-specific clinical signs. In the current global era, the incidence of duodenal infection/inflammation caused by T. whipplei in Korea may has been underestimated. Here we estimated the prevalence of T. whipplei in duodenal biopsy tissues of Koreans using real-time PCRs (RT-PCRs). A total of 252 duodenal biopsy tissues were collected from Korean patients who underwent esophagogastroduodenoscopy and duodenal biopsy. DNA extracted from the duodenal biopsy tissues was analyzed using three RT-PCRs targeting T. whipplei-specific regions of the 16S-23S rRNA intergenic spacer, hsp65, and Dig15 in parallel. In the samples positive in RT-PCRs, direct sequencing was performed for each RT-PCR target. The prevalence of T. whipplei was estimated based on the RT-PCR and sequencing results. Among the analyzed samples, T. whipplei was not detected. The prevalence of T. whipplei in duodenal biopsy tissues of Koreans was estimated to be less than 0.4%. This is the first study to attempt to detect T. whipplei in duodenal biopsy tissues of Koreans and estimate its prevalence. Our findings infer that while T. whipplei carriers exist in Korea, the incidence of duodenal infection/inflammation caused by T. whipplei is extremely rare.

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BACKGROUND: Satellite repeats are one of the most rapidly evolving components in eukaryotic genomes and play vital roles in genome regulation, genome evolution, and speciation. As a consequence, the composition, abundance and chromosome distribution of satellite repeats often exhibit variability across various species, genome, and even individual chromosomes. However, we know little about the satellite repeat evolution in allopolyploid genomes. RESULTS: In this study, we investigated the satellite repeat signature in five okra (Abelmoschus esculentus) accessions using genomic and cytogenetic methods. In each of the five accessions, we identified eight satellite repeats, which exhibited a significant level of intraspecific conservation. Through fluorescence in situ hybridization (FISH) experiments, we observed that the satellite repeats generated multiple signals and exhibited variations in copy number across chromosomes. Intriguingly, we found that five satellite repeats were interspersed with centromeric retrotransposons, signifying their involvement in centromeric satellite repeat identity. We confirmed subgenome-biased amplification patterns of these satellite repeats through existing genome assemblies or dual-color FISH, indicating their distinct dynamic evolution in the allotetraploid okra subgenome. Moreover, we observed the presence of multiple chromosomes harboring the 35 S rDNA loci, alongside another chromosomal pair carrying the 5 S rDNA loci in okra using FISH assay. Remarkably, the intensity of 35 S rDNA hybridization signals varied among chromosomes, with the signals predominantly localized within regions of relatively weak DAPI staining, associated with GC-rich heterochromatin regions. Finally, we observed a similar localization pattern between 35 S rDNA and three satellite repeats with high GC content and confirmed their origin in the intergenic spacer region of the 35 S rDNA. CONCLUSIONS: Our findings uncover a unique satellite repeat signature in the allotetraploid okra, contributing to our understanding of the composition, abundance, and chromosomal distribution of satellite repeats in allopolyploid genomes, further enriching our understanding of their evolutionary dynamics in complex allopolyploid genomes.

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(1) Background: The entomopathogenic fungus Metarhizium anisopliae sensu lato forms a species complex, comprising a tight cluster made up of four species, namely M. anisopliae sensu stricto, M. pinghaense, M. robertsii and M. brunneum. Unambiguous species delineation within this "PARB clade" that enables both the taxonomic assignment of new isolates and the identification of potentially new species is highly solicited. (2) Methods: Species-discriminating primer pairs targeting the ribosomal intergenic spacer (rIGS) sequence were designed and a diagnostic PCR protocol established. A partial rIGS sequence, referred to as rIGS-ID800, was introduced as a molecular taxonomic marker for PARB species delineation. (3) Results: PARB species from a validation strain set not implied in primer design were clearly discriminated using the diagnostic PCR protocol developed. Using rIGS-ID800 as a single sequence taxonomic marker gave rise to a higher resolution and statistically better supported delineation of PARB clade species. (4) Conclusions: Reliable species discrimination within the Metarhizium PARB clade is possible through both sequencing-independent diagnostic PCR and sequencing-dependent single marker comparison, both based on the rIGS marker.

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Sampling surveys of Angelica acutiloba and A. acutiloba var. iwatensis, which are medicinal plants endemic to Japan, were conducted in the Chubu region in the central area of the main island of Japan. A. acutiloba grows in riverbeds in mountainous areas, while A. acutiloba. var. iwatensis grows on slopes near mountain ridges at 1000 m above sea level or on constantly collapsing rocky slopes and bare fields on developed land along asphalt roads in valleys of mountainous areas. Specimens of two wild Angelica species collected in this region were examined for maternal lineage by DNA polymorphism analysis of the atpF-atpA region for chloroplast DNA using direct sequencing and genomic component analysis by genome-wide SNP using MIG-seq. In this study area, while all A. acutiloba populations were monophyletic in both maternal and ancestral lineages, A. acutiloba var. iwatensis were genetically heterogeneous due to being composed of three maternal and three ancestral lineages to various degrees. In addition, a natural hybrid population with maternal lineage presumed to be A. acutiloba and paternal lineage A. acutiloba var. iwatensis was also found. In the present study, we report that the combined method of atpF-atpA and MIG-seq analyses is a useful tool for determining the population genetic structure of two wild Angelica species and for identifying hybrids.

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The genes coding for the rRNAs seem evolutionary conserved on the first glance, but astonish one with their variability in the structure and a variety of functions on closer examination. The non-coding parts of rDNA contain regulatory elements, protein binding sites, pseudogenes, repetitive sequences, and microRNA genes. Ribosomal intergenic spacers are not only in charge with the nucleolus morphology and functioning, namely, the rRNA expression and ribosome biogenesis, but also control nuclear chromatin formation thus mediating cell differentiation. The alterations in the expression of these non-coding regions of rDNA in response to environmental stimuli underlie the keen sense of a cell to various types of stressors. Malfunctioning of this process may result in a wide range of pathologies from oncology to neurodegenerative disease and mental illness. Here, we observe to-date materials on the structure and transcription of the ribosomal intergenic spacer in humans and its role in rRNA expression, in-born disease development, and cancer.

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Lamiinae is the largest subfamily of the Cerambycidae (longhorn beetles), with approximately 21,863 described species. Previous phylogenetic studies of Lamiinae showed that this subfamily was monophyletic, but the relationship between the tribes of Lamiinae is still controversial. Partial molecular data and species morphological characteristics are not sufficient to resolve species phylogenetic studies perfectly. At the same time, the full mitochondrial genome contains more comprehensive genetic data. Benefiting from the development of next-generation sequencing (NGS), mitochondrial genomes can be easily acquired and used as reliable molecular markers to investigate phylogenetic relationships within Cerambycidae. Using NGS technology, we obtained 11 mitochondrial genome sequences of Lamiinae species. Based on this newly generated mitochondrial genome dataset matrix, we reconstructed the phylogeny of Lamiinae. The Bayesian Inference and Maximum Likelihood analyses strongly support the monophyly of four tribes (Lamiini, Batocerini, Mesosini, and Saperdini), whereas the tribe Acanthocinini was identified as paraphyletic. Other mitochondrial structural features were also observed: the start codon in the nad1 gene of all 11 mitochondrial genomes is TTG; 17-22 bp intergenic spacers (IGS) with a 'TACTA' motif were found between trnS2 and nad1. Moreover, two long IGS were found in Mesosa myops and Batocera sp. Tandem repeats were found in the IGS of Batocera sp.

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Opportunistic infections due to Cryptococcus neoformans and C. gattii species complexes continue to rise unabated among HIV/AIDS patients, despite improved antifungal therapies. Here, we collected a total of 20 environmental and 25 presumptive clinical cryptococcal isolates from cerebrospinal fluid (CSF) samples of 175 patients enrolled in an ongoing clinical trial Ambition 1 Project (Botswana-Harvard Partnership). Identity confirmation of the isolates was done using MALDI-TOF MS and PCR. We describe the diversity of the isolates by PCR fingerprinting and sequencing (Oxford Nanopore Technology) of the intergenic spacer region. Mating types of the isolates were determined by amplification of the MAT locus. We report an unusual prevalence of 42.1% of C. neoformans x C. deneoformans hybrids Serotype AD (n = 16), followed by 39.5% of C. neoformans Serotype A (n = 15), 5.3% of C. deneoformans, Serotype D (n = 2), 7.9% of C. gattii (n = 3), and 5.3% of C. tetragattii (n = 2) in 38 representative isolates that have been characterized. Mating type-specific PCR performed on 38 representative environmental and clinical isolates revealed that 16 (42.1%) were MATa/MATα hybrids, 17 (44.7%) were MATα, and five (13.2%) possessed MATa mating type. We used conventional and NGS platforms to demonstrate a potential link between environmental and clinical isolates and lay a foundation to further describe mating patterns/history in Botswana.

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BACKGROUND: Fruit flies (Diptera: Tephritidae) comprise species of agricultural and economic importance. Five such fruit fly species are known to affect commercial fruit production and export in South Africa: Ceratitis capitata, Ceratitis cosyra, Ceratitis rosa, Ceratitis quilicii, and Bactrocera dorsalis. Management practices for these pests include monitoring, application of pest control products, post-harvest disinfestation measures and inspection of consignments both prior to shipment and at ports of entry. In activities relating to monitoring and inspection, accurate identification of these pests to species level is required. While morphological keys for adult stages of these fruit fly species have been well developed, morphological keys for earlier life stages remain problematic. In instances where closely related species cannot be reliably distinguished morphologically, there is a need for molecular tools to assist in identifying these five fruit fly species during surveillance practices, where sequencing-based approaches would be beneficial. RESULTS: Two complete mitochondrial genomes were assembled for each fruit fly species investigated using high throughput sequencing data generated in this study. A single primer set was designed to amplify a region between tRNAile and tRNAmet. The amplicon consists of a partial segment of tRNAile, intergenic region I (tRNAile - tRNAgln), the complete sequence of tRNAgln, intergenic region II (tRNAgln - tRNAmet), and a partial segment of tRNAmet. PCR amplicons were generated for 20 specimens of each species, five of which were colony adult males, five colony larvae, and 10 wild, trap-collected specimens. Upon analysis of the amplicon, intergenic region I was identified as the most informative region, allowing for unambiguous identification of the five fruit fly species. The similarity in intergenic region II was too high between C. rosa and C. quilicii for accurate differentiation of these species. CONCLUSION: The identity of all five fruit flies investigated in this study can be determined through sequence analysis of the mitochondrial intergenic regions. Within the target amplicon, intergenic region I (tRNAile - tRNAgln) shows interspecific variation sufficient for species differentiation based on multiple sequence alignment. The variation in the length of intergenic region I is proposed as a potential tool for accurately identifying these five fruit flies in South Africa.

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In order to investigate the relationship between the chemical composition of essential oils and haplotypes of the psbA-trnH intergenic spacer region of chloroplast DNA (psbA-trnH) in Valerianae Fauriei Radix (Japanese Valerian; JV), we analyzed the DNA sequence and GC-MS metabolome of JV from Japanese markets and of herbal specimens from related species. DNA analysis revealed that JV products from Japan consisted of three haplotypes, namely AH-1, -2 and -5 reported in our previous study. The GC-MS metabolome revealed five chemotypes (J1, J2, C, K and O), of which J1, J2 and C were detected in the JV products from Japan. Chemotypes J1 and J2, with kessyl glycol diacetate (KGD) as the main volatile component, were found in the products of Japanese origin whereas chemotype C, with 1-O-acetyl-2,10-bisaboladiene-1,6-diol (ABD), was found in the products of Chinese and Korean origin. The haplotypes were correlated with the chemotypes: haplotype AH-1 for chemotype J1, AH-2 for chemotype J2 and AH-5 for chemotype C, suggesting that the chemical diversity of JV is not attributed to the environmental factors rather to the genetic factors. Since KGD and ABD were reported to have sedative effects and nerve growth factor (NGF)-potentiating effects, respectively, understanding the chemotypes and selecting an appropriate one would be important for the application of JV. The psbA-trnH haplotypes could be useful DNA markers for the quality control and standardization of JV.

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Response of culturable microbes on the surface of apples treated with slightly alkaline electrolyzed water (SAIEW) is largely unexplored. Thus, the aim of this study was to characterize culturable microbes on the surface of SAIEW treated 'Granny Smith' apples using conventional and molecular approach. Results showed that SAIEW treatments and storage duration influenced culturable microbes isolated from the surface of 'Granny Smith' apples stored at 5 °C for 21 days. Enterobacterial repetitive intergenic consensus (ERIC-PCR) analysis distinctively identified 27 groups of bacteria from 56 plate isolates. Using random amplified polymorphic DNA (RAPD-PCR) typing and RAPD1283 primers, 10 distinct band patterns were identified from 30 fungal isolates. Sequencing of 16S rRNA and intergenic spacer (ITS1 and ITS4) region, identified eight bacteria and four fungi, respectively, to species level. Study showed that SAIEW treatment inhibited growth of Staphylococcus epidermidis, S. capitis, Ochrobactrum soli, and Aspergillus inuii on the surface apples during storage. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01148-2.

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The vast majority (approximately 90%) of Lepidoptera species belong to moths whose phylogeny has been widely discussed and highly controversial. For the further understanding of phylogenetic relationships of moths, nineteen nearly complete mitochondrial genomes (mitogenomes) of moths involved in six major lineages were sequenced and characterized. These mitogenomes ranged from 15,177 bp (Cyclidia fractifasciata) to 15,749 bp (Ophthalmitis albosignaria) in length, comprising of the core 37 mitochondrial genes (13 protein-coding genes (PCGs) + 22 tRNAs + two rRNAs) and an incomplete control region. The order and orientation of genes showed the same pattern and the gene order of trnM-trnI-trnQ showed a typical rearrangement of Lepidoptera compared with the ancestral order of trnI-trnQ-trnM. Among these 13 PCGs, ATP8 exhibited the fastest evolutionary rate, and Drepanidae showed the highest average evolutionary rate among six families involved in 66 species. The phylogenetic analyses based on the dataset of 13 PCGs suggested the relationship of (Notodontidae + (Noctuidae + Erebidae)) + (Geometridae + (Sphingidae + Drepanidae)), which suggested a slightly different pattern from previous studies. Most groups were well defined in the subfamily level except Erebidae, which was not fully consistent across bayesian and maximum likelihood methods. Several formerly unassigned tribes of Geometridae were suggested based on mitogenome sequences despite a not very strong support in partial nodes. The study of mitogenomes of these moths can provide fundamental information of mitogenome architecture, and the phylogenetic position of moths, and contributes to further phylogeographical studies and the biological control of pests.

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Epeorus Eaton, 1881 is a diverse mayfly genus in Heptageniidae comprising more than 100 species which are further divided into nine subgenera and several species groups. However, the classification and the phylogenetic relationships among them are still uncertain. Here, 15 complete mitochondrial genomes of Epeorus were sequenced and compared together with six available ones of same genus in the NCBI database. Based on morphological classification, the 21 mitogenomes were classified into six subgenera (Proepeorus, Epeorus s.str., Belovius, Iron, Caucasiron and Siniron) and four species groups (G1, G2, montanus and longimanus). Among all analyzed mitogenomes, the gene rearrangement of trnI-trnM-trnQ-NCR-ND2 was first found occurring in three species of group G1, whereas the gene block trnI-trnM-trnQ-trnM-ND2 was observed in all other mitogenomes of Epeorus. Furthermore, the genetic composition and codon usage of species in group G1 were also significantly different from all other Epeorus species, except group longimanus. The intergenic spacer between trnA and trnR, which has the stem-loop secondary structure, occurred in all 21 mitogenomes, and the sequences of stems and loops were conserved within species groups. Furthermore, the phylogenetic analyses strongly support the monophyly of all species groups, although three of six recognized subgenera Proepeorus, Belovius, and Iron, were shown as the non-monophyletic groups.

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Hemp (Cannabis sativa L.) is a valuable crop and model plant for studying sex chromosomes. The scientific interest in the plant has led to its whole genome sequencing and the determination of its cytogenetic characteristics. A range of cytogenetic markers (subtelomeric repeat CS-1, 5S rDNA, and 45S rDNA) has been mapped onto hemp's chromosomes by fluorescent in situ hybridization (FISH). In this study, another cytogenetic marker (the tandem repeat CS-237, with a 237 bp monomer) was found, studied, and localized on chromosomes by FISH. The signal distribution and karyotyping revealed that the CS-237 probe was localized in chromosome 6 with one hybridization site and in chromosome 8 with two hybridization sites, one of which colocalizes with the 45S rDNA probe (with which a nucleolus organizer region, NOR, was detected). A BLAST analysis of the genomic data and PCR experiments showed that the modified CS-237 monomers (delCS-237, 208 bp in size) were present in the intergenic spacers (IGSs) of hemp 45S rDNA monomers. Such a feature was firstly observed in Cannabaceae species. However, IGS-linked DNA repeats were found in several plant species of other families (Fabaceae, Solanaceae, and Asteraceae). This phenomenon is discussed in this article. The example of CS-237 may be useful for further studying the phenomenon as well as for the physical mapping of hemp chromosomes.

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The aim of the present study is to establish a method, based on sequence analysis of the helix 54 of 23S rRNA gene, to identify clinical relevant strains belonging to viridans group streptococci (VGS). A set of 25 randomly selected clinical isolates of alpha-hemolytic streptococci from upper respiratory tract were characterized by the routine phenotypic methods (API 20 Strep test). Molecular characterization was assessed by genotypic analysis of the nucleotide sequence of the helix 54 of 23S rRNA and Intergenic spacer region 16S23S. Partial sequencing of the gdh gene was used on 10 strains of mitis group. Sequence variations of the helix 54 allowed the identification of strains to group level and even to species level for certain strains within sanguinis and anginosus groups. Infact, species identification was ambiguous for some strains belonged to the salivarius group (of VGS16 to VGS20) and the mitis group (of VGS1 to VGS14). These results are almost similar to those obtained by sequencing the 16S23S intergenic region. Thus, we use the gdh gene sequencing for the identification of strains, not recognized, within the mitis group. The results generated herein indicate that no single methodology can be used to provide an accurate identification to the species level of all VGS, although nucleotide sequence analysis of the helix 54 of 23S rRNA gene proved to be a reliable method for the identification of VGS to the group level and even to the species level within sanguinis and anginosus groups.

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The present study was designed to characterize phenotypically and genotypically a Trueperella (T.) pecoris strain isolated from necrotic vestibulitis of a 10-year-old camel (Camelus dromedarius). The species identity of T. pecoris 203/7 investigated in the present study could be confirmed by phenotypic properties and by phylogenetic analyses based on partial sequencing of the 16S ribosomal RNA (rRNA) gene, the 16S-23S rDNA intergenic spacer region, the glyceraldehyde 3-phosphate dehydrogenase encoding gene gap, elongation factor Tu encoding gene tuf and the target gene rpoB encoding the ß-subunit of bacterial RNA polymerase. T. pecoris strain 203/7 was grouped within the genus Trueperella in the family Arcanobacteriaceae. The 16S rRNA gene analysis showed a sequence identity of 99·9% to reference strain T. pecoris DSM 111392T . The present isolate was clearly identified as T. pecoris, the most recently described species of the genus Trueperella. Strain T. pecoris 203/7 was isolated in moderate numbers from necrotic vestibulitis of the camel and could be of some importance for the infectious process. However, the investigated strain represents the first isolation of T. pecoris from a camel.

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Staphylococcus aureus causes a foodborne intoxication due to the production of enterotoxins and shows antimicrobial resistance, as in the case of methicillin-resistant strains (MRSA). Herein, we analyzed 207 ready-to-eat foods collected in Algeria, reporting a S. aureus prevalence of 23.2% (48/207) and respective loads of coagulase positive staphylococci (CPS) ranging from 1.00 ± 0.5 to 5.11 ± 0.24 Log CFU/g. The 48 S. aureus isolates were widely characterized by staphylococcal enterotoxin gene (SEg)-typing and 16S-23S rDNA intergenic spacer region (ISR)-PCR, as well as by detecting tst and mecA genes, genetic determinants of toxic shock syndrome toxin-1 and methicillin resistance, respectively. We found that the S. aureus isolates belonged to seven different SEg-types harboring the following combinations of genes: (1) selW, selX; (2) egc (seG, seI, seM, seN, seO), selW, selX; (3) seA, seH, seK, seQ, selW, selX; (4) seB, selW, selX; (5) seD, selJ, seR, selW, selX; (6) seH, selW, selX, selY; and (7) seA, egc, selW, selX, while among these, 2.1% and 4.2% were tst- and mecA- (staphylococcal chromosomal cassette mec-type IV) positive, respectively. Selected strains belonging to the 12 detected ISR-types were resistant towards antimicrobials including benzylpenicillin, ofloxacin, erythromycin, lincomycin, tetracyclin, kanamycin, oxacillin, and cefoxitin; 8.3% (1/12) were confirmed as MRSA and 16.7% (2/12) were multidrug resistant. The present study shows the heterogeneity of the S. aureus population in Algerian ready-to-eat foods as for their toxigenic potential and antimicrobial resistance, shedding the light on the quality and safety related to the consume of ready-to-eat foods in Algeria.

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