Challenges to Explore Genus Streptomyces in Ethiopia-A Mini Review

Genus Streptomyces is gram-positive bacteria that grow in various environments. It has plentiful biotechnological attributes on the area of agricultural, bioremediation, biofuel, clinical, food, industrial, medical, pharmaceutical, and veterinary. The aim of the review is to frontward challenges to explore potent Streptomyces species in the case of Ethiopia. There is lack of the extent and quality of the genetic research regarding to genome sequence, bioactive compound discovery, and genetic manipulation. Their functional and structural diversity is not full studied. To find a new Streptomyces species: Culture media formulation and optimization as wells culture-independent method like Next Generation Sequencing approach should incorporate at national level.

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Angucycline-like Aromatic Polyketide from a Novel Streptomyces Species Reveals Freshwater Snail Physa acuta as Underexplored Reservoir for Antibiotic-Producing Actinomycetes

Antibiotics ◽

10.3390/antibiotics10010022 ◽

2020 ◽

Vol 10 (1) ◽

pp. 22

Author(s):

Nasim Safaei ◽

Yvonne Mast ◽

Michael Steinert ◽

Katharina Huber ◽

Boyke Bunk ◽

...

Keyword(s):

High Throughput Sequencing ◽

Genome Mining ◽

Freshwater Snail ◽

Whole Genome Sequence ◽

Phylogenomic Analysis ◽

Ionization Mass ◽

Gram Positive ◽

Streptomyces Species ◽

Genus Streptomyces ◽

Physa Acuta

Antibiotic producers have mainly been isolated from soil, which often has led to the rediscovery of known compounds. In this study, we identified the freshwater snail Physa acuta as an unexplored source for new antibiotic producers. The bacterial diversity associated with the snail was characterized by a metagenomic approach using cultivation-independent high-throughput sequencing. Although Actinobacteria represented only 2% of the bacterial community, the focus was laid on the isolation of the genus Streptomyces due to its potential to produce antibiotics. Three Streptomyces strains (7NS1, 7NS2 and 7NS3) were isolated from P. acuta, and the antimicrobial activity of the crude extracts were tested against a selection of Gram-positive and Gram-negative bacteria and fungi. 7NS3 showed the strongest activity against Gram-positive bacteria and, thus, was selected for genome sequencing and a phylogenomic analysis. 7NS3 represents a novel Streptomyces species, which was deposited as Streptomyces sp. DSM 110735 at the Leibniz Institute-German Collection of Microorganisms and Cell Cultures (DSMZ). Bioassay-guided high-performance liquid chromatography (HPLC) and high-resolution electrospray ionization-mass spectrometry (HR-ESI-MS) analyses of crude extract fractions resulted in the detection of four compounds, one of which matched the compound characteristics of emycin A, an angucycline-like aromatic polyketide. Genome mining studies based on the whole-genome sequence of 7NS3 resulted in the identification of a gene cluster potentially coding for emycin A biosynthesis. Our study demonstrates that freshwater snails like P. acuta can represent promising reservoirs for the isolation of new antibiotic-producing actinobacterial species.

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Future directions for the discovery of antibiotics from actinomycete bacteria

Emerging Topics in Life Sciences ◽

10.1042/etls20160014 ◽

2017 ◽

Vol 1 (1) ◽

pp. 1-12 ◽

Cited By ~ 8

Author(s):

Rebecca Devine ◽

Matthew I. Hutchings ◽

Neil A. Holmes

Keyword(s):

New Technologies ◽

Gene Clusters ◽

Biosynthetic Gene Clusters ◽

Future Directions ◽

Streptomyces Species ◽

Genus Streptomyces ◽

New Antibiotics ◽

The Uk ◽

Almost All ◽

New Generation

Antimicrobial resistance (AMR) is a growing societal problem, and without new anti-infective drugs, the UK government-commissioned O'Neil report has predicted that infectious disease will claim the lives of an additional 10 million people a year worldwide by 2050. Almost all the antibiotics currently in clinical use are derived from the secondary metabolites of a group of filamentous soil bacteria called actinomycetes, most notably in the genus Streptomyces. Unfortunately, the discovery of these strains and their natural products (NPs) peaked in the 1950s and was then largely abandoned, partly due to the repeated rediscovery of known strains and compounds. Attention turned instead to rational target-based drug design, but this was largely unsuccessful and few new antibiotics have made it to clinic in the last 60 years. In the early 2000s, however, genome sequencing of the first Streptomyces species reinvigorated interest in NP discovery because it revealed the presence of numerous cryptic NP biosynthetic gene clusters that are not expressed in the laboratory. Here, we describe how the use of new technologies, including improved culture-dependent and -independent techniques, combined with searching underexplored environments, promises to identify a new generation of NP antibiotics from actinomycete bacteria.

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Detergent Plants of Northern Thailand: Potential Sources of Natural Saponins

10.20944/preprints201811.0272.v1 ◽

2018 ◽

Author(s):

Jiratchaya Wisetkomolmat ◽

Pongsakorn Suppakittpaisarn ◽

Sarana Rose Sommano

Keyword(s):

Plant Species ◽

Physiological Mechanism ◽

Structural Diversity ◽

Bioactive Compound ◽

Biological Properties ◽

Industrial Applications ◽

Natural Forests ◽

Northern Thailand ◽

Foaming Agents ◽

Plant Environment

The natural forests of Northern Thailand are the mother source of many utilisable natural products because of their diverse flora and fauna. Among many plant species found within Northern Thai forests, detergent plants are known for its distinctive cleansing properties. Several local species of detergent plants in Thailand are traditionally used by the locals and indigenous people. However, these plants may become extinct because their habitats have been replaced by industrial agriculture, and their uses have been replaced by chemically synthesised detergents. Researchers need to study and communicate the biology, phytochemistry, and the importance of these plants to conserve natural biodiversity of Northern Thailand. Of many utilisable detergent phytochemicals, natural saponins are known as bio-surfactant and foaming agents. Their physiochemical and biological properties feature structural diversity, which leads to many industrial applications.  In this review, we explained the term “detergent” from the physiological mechanism perspective and the detergent effects of saponin.  We also compiled a list of Thai local plants with cleansing properties focusing on the saponin-containing plants. Future studies should investigate information relative to plant environment, ethnobotanical data and bioactive compound content of these plants. The knowledge acquired from this study will promote the maintenance of the local biodiversity and the conservation of the detergent plant species found in Thailand.

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Adjustment of Mineral Elements in the Culture Medium for the Micropropagation of Three Vriesea Bromeliads from the Brazilian Atlantic Forest: The Importance of Calcium

HortScience ◽

10.21273/hortsci.44.1.106 ◽

2009 ◽

Vol 44 (1) ◽

pp. 106-112 ◽

Cited By ~ 15

Author(s):

Alice Noemí Aranda-Peres ◽

Lázaro Eustáquio Pereira Peres ◽

Edson Namita Higashi ◽

Adriana Pinheiro Martinelli

Keyword(s):

New Media ◽

Mineral Composition ◽

Culture Media ◽

Dry Weight ◽

Defined Medium ◽

Ms Medium ◽

Media Formulation ◽

Half Strength

Many different species of Bromeliaceae are endangered and their conservation requires specific knowledge of their growth habits and propagation. In vitro culture of bromeliads is an important method for efficient clonal propagation and in vitro seed germination can be used to maintain genetic variability. The present work aims to evaluate the in vitro growth and nutrient concentration in leaves of the epiphyte bromeliads Vriesea friburguensis Mez, Vriesea hieroglyphica (Carrière) E. Morren, and Vriesea unilateralis Mez, which exhibit slow rates of growth in vivo and in vitro. Initially, we compared the endogenous mineral composition of bromeliad plantlets grown in half-strength Murashige and Skoog (MS) medium and the mineral composition considered adequate in the literature. This approach suggested that calcium (Ca) is a critical nutrient and this was considered for new media formulation. Three new culture media were defined in which the main changes to half-strength MS medium were an increase in Ca, magnesium, sulfur, copper, and chloride and a decrease in iron, maintaining the nitrate:ammonium rate at ≈2:1. The main difference among the three new media formulated was Ca concentration, which varied from 1.5 mm in half-strength MS to 3.0, 6.0, and 12 mm in M2, M3, and M4 media, respectively. Consistently, all three species exhibited significantly higher fresh and dry weight on M4, the newly defined medium with the highest level of Ca (12 mm). Leaf nitrogen, potassium, zinc, magnesium, and boron concentrations increased as Ca concentration in the medium increased from 1.5 to 12 mm.

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Genetic Manipulation of Streptomyces Species

Current Protocols in Microbiology ◽

10.1002/9780471729259.mc10e03s19 ◽

2010 ◽

Vol 19 (1) ◽

Cited By ~ 7

Author(s):

S. Eric Nybo ◽

Micah D. Shepherd ◽

Mary A. Bosserman ◽

Jürgen Rohr

Keyword(s):

Genetic Manipulation ◽

Streptomyces Species

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Technical Report: Effect of commercially available PMSG on maturation, fertilization and embryo development of buffalo oocytes in vitro

Reproduction Fertility and Development ◽

10.1071/rd01026 ◽

2001 ◽

Vol 13 (6) ◽

pp. 355 ◽

Cited By ~ 8

Author(s):

P. S. P. Gupta ◽

S. Nandi ◽

B. M. Ravindranatha ◽

P. V. Sarma

Keyword(s):

Embryonic Development ◽

Genetic Manipulation ◽

Culture Media ◽

Cell Monolayer ◽

Basic Research ◽

Cost Effective ◽

Cumulus Cells ◽

Cleavage Rate ◽

Vitro Fertilization

In vitro fertilization (IVF) technology provides an opportunity to produce embryos for genetic manipulation, embryo transfer and basic research in developmental physiology, and can be exploited for emerging biotechnologies such as transgenesis and cloning. In the present study, the effects of different concentrations of commercially available pregnant mare serum gonadotrophin (PMSG) (Folligon; Intervet, International B.V., Boxmeer, Holland) in oocyte culture media, on maturation, fertilization and embryonic development of buffalo oocytes in vitro were investigated. Oocytes aspirated from abattoir-derived ovaries were cultured in media containing TCM-199 + PMSG at 0, 2.5, 20, 30, 40 and 50 IU mL–1 in presence or absence of steer serum (10%) for 24 h in a CO2 incubator. The maturation rate was assessed on the basis of degree of expansion of cumulus cells. The matured oocytes were inseminated with 9–10 x 106 spermatozoa mL–1 in Brackett and Oliphant medium and the cleavage rate was recorded 40–42 h after insemination. Uncleaved oocytes were stained with aceto-orcein for evaluation of fertilization rates. The cleaved embryos were further cultured in TCM-199 + 10% steer serum on buffalo oviducal cell monolayer for 7 days. Maturation, fertilization, cleavage and embryonic development were significantly higher (P<0.05) in oocytes cultured in TCM-199 + 10% steer serum supplemented with 40 and 50 IU PMSG mL–1. It is concluded that commercially available PMSG can effectively be used in place of pure follicle-stimulating hormone for in vitro maturation of buffalo oocytes, making it cost effective for IVF studies.

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Isolation and Characterization of Plant-Pathogenic Streptomyces Species Associated with Common Scab-Infected Potato Tubers in Newfoundland

Phytopathology ◽

10.1094/phyto-05-15-0125-r ◽

2016 ◽

Vol 106 (2) ◽

pp. 123-131 ◽

Cited By ~ 15

Author(s):

Joanna K. Fyans ◽

Luke Bown ◽

Dawn R. D. Bignell

Keyword(s):

Common Scab ◽

Virulence Gene ◽

Potato Scab ◽

Potato Tubers ◽

Streptomyces Species ◽

Genus Streptomyces ◽

Thaxtomin A ◽

Streptomyces Spp ◽

Putative Virulence Gene ◽

Isolation And Characterization

Potato common scab (CS) is an economically important crop disease that is caused by several members of the genus Streptomyces. In this study, we characterized the plant-pathogenic Streptomyces spp. associated with CS-infected potato tubers harvested in Newfoundland, Canada. A total of 17 pathogenic Streptomyces isolates were recovered from potato scab lesions, of which eight were determined to be most similar to the known CS pathogen S. europaeiscabiei. All eight S. europaeiscabiei isolates were found to produce the thaxtomin A phytotoxin and to harbor the nec1 virulence gene, and most also carry the putative virulence gene tomA. The remaining isolates appear to be novel pathogenic species that do not produce thaxtomin A, and only two of these isolates were determined to harbor the nec1 or tomA genes. Of the non-thaxtomin-producing isolates, strain 11-1-2 was shown to exhibit a severe pathogenic phenotype against different plant hosts and to produce a novel, secreted phytotoxic substance. This is the first report documenting the plant-pathogenic Streptomyces spp. associated with CS disease in Newfoundland. Furthermore, our findings provide further evidence that phytotoxins other than thaxtomin A may also contribute to the development of CS by Streptomyces spp.

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A New Strain of Streptomyces Causing Common Scab in Potato

Plant Disease ◽

10.1094/pdis-91-4-0352 ◽

2007 ◽

Vol 91 (4) ◽

pp. 352-359 ◽

Cited By ~ 23

Author(s):

Leslie A. Wanner

Keyword(s):

16S Rdna ◽

Horizontal Transfer ◽

Common Scab ◽

The United States ◽

Streptomyces Species ◽

Genus Streptomyces ◽

16S Rdna Sequence ◽

Genes Encoding ◽

Pathogenicity Determinant ◽

Serious Disease

Common scab is a serious disease of potatoes (Solanum tuberosum) and other root and tuber crops, affecting the quality and market value of these crops. The disease is caused by gram-positive soil bacteria in the genus Streptomyces. A new common scab-causing streptomycete was isolated from scabby potatoes originating in southeastern Idaho. Research has supported a model of horizontal transfer of pathogenicity determinants among streptomycetes, and the new strain has hallmarks of the recently characterized Streptomyces pathogenicity island (PAI); it has genes encoding the synthetase for the pathogenicity determinant thaxtomin and for a second pathogenicity factor, tomatinase, although it lacks a third gene characteristic of the Streptomyces PAI, the nec1 gene. The new strain has a unique 16s rDNA gene sequence closely related to those of other pathogenic Streptomyces species. This 16s rDNA sequence was also found in isolates lacking a PAI, suggesting that the new pathogenic strain arose by horizontal transfer of a PAI into a saprophytic streptomycete. Isolates of the new strain are pathogenic on radish and potato, and are more virulent than the S. scabies type strain. In addition to scab lesions on potato tubers, lesions were also seen on underground stems and stolons. This new strain represents additional complexity in the pathogenic strains causing plant disease in the United States.

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Streptomyces Species Associated with Fissure Scab of Potato in South Africa Including Description of S. Resiliuntiscabiei Sp. Nov.

10.21203/rs.3.rs-326303/v1 ◽

2021 ◽

Author(s):

Elsie Margaretha Cruywagen ◽

Rian Pierneef ◽

Kgothatso Andronicah Chauke ◽

Brightness Zama Nkosi ◽

David Labeda ◽

...

Keyword(s):

South Africa ◽

Culture Media ◽

Phylogenetic Analyses ◽

Housekeeping Genes ◽

Potato Tubers ◽

Streptomyces Species ◽

Culture Morphology ◽

New Type ◽

Genome Analyses ◽

Phenotypic Tests

Abstract Streptomyces species are the causal agents of several scab diseases on potato tubers. A new type of scab symptom, caused by Streptomyces species, was observed in South Africa from 2010 onwards. The disease was initially thought to be caused by a single Streptomyces species, however, subsequent isolations from similar symptoms on other potato tubers revealed diversity of the Streptomyces isolates. The objective of this study was to characterise these isolates in order to determine which species are involved in the disease. This was done by sequencing and phylogenetic analyses of the 16S rDNA as well as five housekeeping genes, investigation of growth on different culture media, standard phenotypic tests and scanning electron microscopy of culture morphology. The presence of the pathogenicity island (PAI) present in plant pathogenic Streptomyces species was also investigated. The genomes of eight isolates selected from the three main clades identified, were sequenced and annotated to further clarify species boundaries. Two isolates of each of the three main clades were also inoculated onto susceptible potato cultivars in order to establish the pathogenicity of the species. The results of the phylogenetic and genome analyses revealed that there are three main species involved, namely, S. werraensis, S. pseudogriseolus and a novel Streptomyces species that is described here as Streptomyces resiliuntiscabiei sp. nov. The glasshouse trial results showed that all three of the Streptomyces species are capable of producing fissure scab symptoms. None of the Streptomyces isolates from fissure scab contained the full PAI and the mechanism of disease initiation still needs to be determined.

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Efisiensi Mikropropagasi Pisang Kepok Amorang melalui Modifikasi Formula Media dan Temperatur

Jurnal AgroBiogen ◽

10.21082/jbio.v6n2.2010.p91-100 ◽

2016 ◽

Vol 6 (2) ◽

pp. 91

Author(s):

Yati Supriati

Keyword(s):

In Vitro Culture ◽

Incubation Temperature ◽

Culture Media ◽

Shoot Multiplication ◽

Root Induction ◽

Incubation Condition ◽

Growth Environment ◽

Media Formulation ◽

The Media

Micropropagation Efficiency of Banana cv Kepok Amorang through Modifications of Culture Media and Incubation Temperature. Yati Supriati. The budless banana cv Kepok Amorang is potentially commercialized due to its sweet taste and does not have flower bud, hence reduced the potential of being infected by the blood disease pathogen. Enhancement of banana industry needs continuous supplies of large number banana seedlings. In vitro culture enable the production of seedlings in a large scale, uniform, quick. The research aims: (1) to formulate an efficient medium for in vitro multiplication of cv Kepok Amorang shoot, (2) to identify efficient growth environment for in vitro culture of cv Kepok Amorang, and (3) to formulate an efficient culture medium for roots inductions of cv Kepok Amorang. The plant material used was in vitro culture of Kepok cv Amorang, 2 cm in height without leaf and root. The media formulation for shoot multiplication were full strength, half strength, one fourth strength MS media, supplemented with either 1, 3, or 5 ppm IBA. On optimization step, the media tested were MS, Knop, Knop and Heller, Hyponex N, Growmore N, and Rosasol N containing of 1 ppm BA. The explants were incubated in culture room with 8, 12, and 16 hours photoperiod with temperatures 30oC (non air conditioned) and 25oC (air conditioned). The root induction trial was done using MS, Knop, Knop and Heller, Hyponex N, Growmore N, and Rosasol N media containing of 1 ppm and 3 ppm IBA. The results showed that the best medium formula for shoot multiplication was ¼ MS + 1 ppm IBA. The best incubation condition was 16 hours photoperiods at 30oC. The best media for root induction was Hyponex 2 g/l + 1 ppm IBA. This culture method reduced cost by Rp 261.7 per plantlet through efficiency of media formulation and electricity use.

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