scholarly journals Isolation and Identification of the Causal Agent of Brown Stalk Rot, A New Disease of Maize in South Africa

Plant Disease ◽  
2007 ◽  
Vol 91 (6) ◽  
pp. 711-718 ◽  
Author(s):  
T. Goszczynska ◽  
W. J. Botha ◽  
S. N. Venter ◽  
T. A. Coutinho
Keyword(s):  
South Africa ◽  
Biochemical Characterization ◽  
Bacterial Species ◽  
Anaerobic Bacteria ◽  
Rrna Gene ◽  
New Disease ◽  
Isolation And Identification ◽  
Stalk Rot ◽  
Pathogenicity Tests ◽  
Internal Browning

During 2004 to 2005, an unreported disease of maize (Zea mays) was observed on commercial fields in the Northwest and Mpumalanga Provinces of South Africa. Infected plants were stunted, with a vertical crack at the first internode. Inside the stem, a dark-brown, narrow lesion was present along the crack. Internal browning inside the stem extended upward, reaching the top internode in some plants. Seed cobs were underdeveloped. Diseased plants were scattered in the fields and 10 to 70% of the crop was affected. Gram-negative, facultatively anaerobic bacteria were consistently isolated from diseased tissues. Pathogenicity tests established that representative strains induced disease symptoms similar to those observed on maize plants in the field. Physiological and biochemical characterization using the API 20E and API 50CHE systems and 16S rRNA gene sequence analyses showed that the strains belonged to the genus Pantoea. The results of these tests also separated the strains into two groups. The first group, giving a positive reaction in the indole test, was similar to Pantoea ananatis. The second group of strains was indole negative and resembled P. agglomerans. The fluorescent amplified fragment length polymorphism (F-AFLP) genomic fingerprints generated by the indole-positive strains and P. ananatis reference strains were similar and clustered together in the dendrogram, confirming that the indole-positive bacteria causing brown stalk rot on maize were P. ananatis. The F-AFLP fingerprints produced by the indole-negative strains were distinctly different from those generated by P. ananatis, P. agglomerans, P. dispersa, P. citrea, P. stewartii subsp. stewartii, and P. stewartii subsp. indologenes. The results indicated that indole-negative bacteria causing brown stalk rot on maize might belong to a previously undescribed species of the genus Pantoea. This is the first report of a new disease on maize, brown stalk rot, caused by two bacterial species, P. ananatis and an undescribed Pantoea sp.

scholarly journals Interpreting Proteobacteria diversity through 16S rRNA analysis in Manasbal Lake, Kashmir

2021 ◽  
Vol 1 (01) ◽  
pp. 7-16
Author(s):  
Sana Shafi ◽  
Suhaib A. Bandh ◽  
Nowsheen Shameem
Keyword(s):  
16S Rrna ◽  
Biochemical Characterization ◽  
Bacterial Species ◽  
Bacterial Community Composition ◽  
Open Water ◽  
Freshwater Ecosystem ◽  
Rrna Gene ◽  
16S Rrna Analysis ◽  
Manasbal Lake ◽  
Spatio Temporal

Bacterial community composition in aquatic ecosystems is of renewed interest for its health as well as the people living in the adjoining areas, and the current work on a freshwater ecosystem in Kashmir Himalayas–the Manasbal Lake was carried out in this backdrop. Water samples were collected from various sampling stations, selected as the zones of special ecological interest and according to the degree of difference in the anthropogenic intrusions in the lake. For identification, the isolated bacterial colonies were subjected to morphological and biochemical characterization, which were further confirmed by targeting their 16S rRNA gene, using 27F and 1492R as the universal bacterial primers. Major bacterial phylum, thus isolated, was proteobacteria with 15 different bacterial species belonging to class alpha-proteobacteria, beta-proteobacteria, and gammaproteobacteria. However, the most diverse class isolated was Alphaproteobacteria comprising seven species followed by Betaproteobacteria comprising six species and Gamma-proteobacteria comprising only two species. The distribution of the bacterial group was seen influenced on a Spatio-temporal scale with the maximum density observed during summer and minimum during winter, further the load was highest for littoral sampling stations in comparison to the open water sites. Proteobacteria are important since they perform basic functions in global transformations of elements. But at the same time, they show close interaction with eukaryotes, both as pathogens and as symbionts.

scholarly journals Isolation and characterisation of endocrine disruptor nonylphenol-using bacteria from South Africa

2017 ◽  
Vol 113 (5/6) ◽  
Author(s):  
Lehlohonolo B. Qhanya ◽  
Ntsane T. Mthakathi ◽  
Charlotte E. Boucher ◽  
Samson S. Mashele ◽  
Chrispian W. Theron ◽  
...  
Keyword(s):  
South Africa ◽  
Bacterial Species ◽  
Endocrine Disrupting Chemicals ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Mpumalanga Province ◽  
Synthetic Chemicals ◽  
Phylogenetic Identification ◽  
Rrna Gene Sequencing

Endocrine disrupting chemicals (EDCs) are synthetic chemicals that alter the function of endocrine systems in animals including humans. EDCs are considered priority pollutants and worldwide research is ongoing to develop bioremediation strategies to remove EDCs from the environment. An understanding of indigenous microorganisms is important to design efficient bioremediation strategies. However, much of the information available on EDCs has been generated from developed regions. Recent studies have revealed the presence of different EDCs in South African natural resources, but, to date, studies analysing the capabilities of microorganisms to utilise/degrade EDCs have not been reported from South Africa. Here, we report for the first time on the isolation and enrichment of six bacterial strains from six different soil samples collected from the Mpumalanga Province, which are capable of utilising EDC nonylphenol as a carbon source. Furthermore, we performed a preliminary characterisation of isolates concerning their phylogenetic identification and capabilities to degrade nonylphenol. Phylogenetic analysis using 16S rRNA gene sequencing revealed that four isolates belonged to Pseudomonas and the remaining two belonged to Enterobacteria and Stenotrophomonas. All six bacterial species showed degradation of nonylphenol in broth cultures, as HPLC analysis revealed 41–46% degradation of nonylphenol 12 h after addition. The results of this study represent the beginning of identification of microorganisms capable of degrading nonylphenol, and pave the way for further exploration of EDC-degrading microorganisms from South Africa.

scholarly journals Phenotypic and molecular characterization of different isolates of Lactobacillus plantarum from four Nigerian fermented foods for use as probiotics in aquaculture

2018 ◽  
Vol 5 (10) ◽  
pp. 329-337
Author(s):  
Daniel Olusegun Diyaolu ◽  
Fatuyi Olanipekun Ekundayo ◽  
Emmanuel Adedayo Fasakin ◽  
Olabode Thomas Adebayo
Keyword(s):  
16S Rrna ◽  
Lactobacillus Plantarum ◽  
Biochemical Characterization ◽  
Bacterial Species ◽  
Fermented Food ◽  
Rrna Gene ◽  
Fermented Foods ◽  
Slight Variation ◽  
16S Rna

This study aimed at identifying Lactobacillus plantarum from fermented maize, sorghum, soyabeans and cassava, using both phenotypic method and 16S RNA sequencing, as well as determining similarity or otherwise among recovered isolates. Biochemical characterization of isolates recovered from these fermented foods revealed that L. plantarum occurred in all fermented food examined, with slight variation in their abilities to ferment some sugars (arabinose, dulbitol and mannitol). These phenotypically identified isolates were also confirmed to be L. plantarum by 16S rRNA sequencing, having close relatedness (> 95%) with other isolates available in the gene bank. However, intragenomic heterogeneity of the 16S rRNA gene was observed among these L. plantarum isolates. The result obtained in this finding pinpoints the need to evaluate the beneficial effects each strain of L. plantarum may possess as promising probiotics, rather than generalising common effects for all strains of this bacterial species.

scholarly journals Isolation, molecular identification and antibiogram profiles of Escherichia coli and Salmonella spp. from diarrhoeic cattle reared in selected areas of Bangladesh

2017 ◽  
Vol 2 (4) ◽  
pp. 587-595
Author(s):  
M Sohidullah ◽  
Md Shahidur Rahman Khan ◽  
Md Shafiqul Islam ◽  
Md Mehedul Islam ◽  
Saifur Rahman ◽  
...  
Keyword(s):  
Bacterial Species ◽  
Research Work ◽  
Clinical Signs ◽  
Rrna Gene ◽  
Biochemical Tests ◽  
Salmonella Spp ◽  
Isolation And Identification ◽  
E Coli ◽  
Field Samples ◽  
Cultural Media

The present research work was undertaken to find out the passive causes of occurrences of diarrhoea in terms of age, sex, season and location differences through isolation and identification of the E. coli and Salmonella spp. using cultural, biochemical and molecular from the field samples of the diarrhoeic cattle and to study the antibiogram profiles of the isolated bacterial species. Considering above purposes, a total of 57 rectal swab samples were collected from the diarrhoeic cattle of Mymensingh sadar, Trishal, Valuka, Natore sadar and Gomostapur, Chapai Nawabganj. Different types of cultural media like Nutrient agar, MacConkey`s (MC) agar, Eosin Methylene Blue (EMB) agar, Salmonella-Shigella (SS) agar, Xylose-Lysine-Deoxycholate (XLD) agar and Blood agar were used to isolate and to study the cultural properties of the E. coli and Salmonella spp. Finally Gram’s staining and different biochemical tests were performed to identify those two bacterial species. Out of 57 samples, 27 were positive for E. coli and 8 were positive for Salmonella spp. On the basis of information from cattle owners and clinical signs the prevalence of diarrhoea was recorded as 30.99% and the pvalue was calculated as 0.001 (p<0.01) which was noted as highly significant. The prevalence percentages of the E. coli and Salmonella spp. were differed depending on different epidemiological parameters like age, sex, season and location. Moreover, the molecular identifications were further confirmed by means of PCR assay using specific primers for E. coli and Salmonella spp. This was done targeting 16S rRNA gene where they were found to be positive showing amplification of 585 bp for E. coli and 574 bp for Salmonella spp. From the study of the antibiogram profiles, it was revealed that E. coli were susceptible to ciprofloxacin, gentamicin and norfloxacin but resistant to tetracycline, erythromycin, amoxicillin and streptomycin whereas Salmonella spp. were susceptible to ciprofloxacin, gentamicin, amoxicillin and streptomycin but resistant to azithromycin, tetracycline and erythromycin. The findings of this research work would certainly help to select the proper antibiotics against diarrhoea in cattle of Bangladesh and to overcome the multi-drug resistant problem of the bacteria.Asian J. Med. Biol. Res. December 2016, 2(4): 587-595

scholarly journals First Report of Leaf Spot Disease of Maize Caused by Pantoea ananatis in Argentina

Plant Disease ◽  
2010 ◽  
Vol 94 (4) ◽  
pp. 487-487 ◽  
Author(s):  
A. M. Alippi ◽  
A. C. López
Keyword(s):  
Pathogenic Bacteria ◽  
Biochemical Characterization ◽  
Anaerobic Bacteria ◽  
The United States ◽  
Leaf Spot Disease ◽  
Rrna Gene ◽  
Sequencing Data ◽  
Pantoea Ananatis ◽  
First Report ◽  
Physiological Tests

From 2007 to 2008, an uncharacterized disease of maize (Zea mays L.) was observed in commercial fields of Laguna Blanca, Formosa, Argentina and from different fields of Santa Fe and Catamarca provinces of Argentina. Symptoms included light-colored necrotic streaks on leaves and tan or white irregular blotches that sometimes were surrounded by reddish purple-to-dark brown margins. Severity of symptoms varied greatly from one field to another. Abundant bacterial streaming was observed from lesions when examined at ×150. Gram-negative, facultatively anaerobic bacteria were consistently isolated from lesions. These formed light yellow-to-orange, glistening, convex colonies on yeast dextrose calcium carbonate agar incubated at 30°C. Ten isolates from ten different symptomatic plants were selected for further study. All isolates were motile, induced a hypersensitive response in tobacco plants, and were oxidase negative. Colonies developed at 37°C. Physiological and biochemical characterization with the API 20E test strips and database (bioMerieux, Buenos Aires, Argentina) showed that the strains belonged to the genus Pantoea. All strains were positive for β-galactosidase, utilized citrate and tartrate, and produced acid from d-glucose, d-mannitol, d-melibiose, l-arabinose, sucrose, meso-inositol, glycerol, d-sorbitol, and amygdalin. All were negative for arginine dihydrolase, lysine decarboxylase, ornithine decarboxylase, tryptophane deaminase, H2S production, urease, and reduction of nitrate to nitrite. Variable results were obtained for indole, gelatinase, and l-rhamnose. Their identity was confirmed by sequencing the 16S rRNA gene strain F327 (GenBank Accession No. GU068363). A BlastN search of GenBank revealed 99% nt identity with strains LMG 20103 (AF364847.1), LMG 20105 (AF364845.1), and LMG 2665 (FJ611815.1) of Pantoea ananatis. Pathogenicity was verified on Z. mays (EM 6079 HX, Dow Morgan) by injection-infiltration of bacterial suspensions at 105 CFU/ml. Controls were infiltrated with sterile distilled water. Plants were kept at 26 ± 3°C in a greenhouse. Symptoms were first detected 15 to 17 days after inoculation and then lesions expanded to resemble natural infections within 30 days. Bacteria were reisolated and the original and reisolated strains were compared by using repetitive sequence-based (rep)-PCR with ERIC primers (1) and fingerprints of the reisolated strains were identical to those of the original strains, thereby fulfilling Koch's postulates. No lesions were observed on controls. Known strains of P. stewartii from the United States (SW2, DC400, DC441, and DC283) were also tested for comparison. On the basis of sequencing data, pathogenicity, and physiological tests, the pathogen was identified as P. ananatis (4). To our knowledge, this is the first report of P. ananatis causing a disease of maize in Argentina, although a similar disease has been reported in Brazil (2) and Mexico (3). References: (1) F. J. Louws et al. Appl. Environ. Microbiol. 60:2286, 1994. (2) L. D. Paccola-Meirelles et al. J. Phytopathol. 149:275, 2001. (3) R. Pérez-y-Terrón et al. Australas. Plant Dis. Notes 4:96, 2009. (4) N. W. Schaad et al., eds. Laboratory Guide for Identification of Plant Pathogenic Bacteria. 3rd ed. The American Phytopathological Society, St. Paul, MN, 2001.

scholarly journals Integrated Metabarcoding and Culturomic-Based Microbiome Profiling of Rice Phyllosphere Reveal Diverse and Functional Bacterial Communities for Blast Disease Suppression

2021 ◽  
Vol 12 ◽  
Author(s):  
Kuleshwar Prasad Sahu ◽  
Asharani Patel ◽  
Mukesh Kumar ◽  
Neelam Sheoran ◽  
Sahil Mehta ◽  
...  
Keyword(s):  
Bacterial Communities ◽  
Rice Blast ◽  
Bacterial Species ◽  
Amplicon Sequencing ◽  
Rice Cultivar ◽  
Disease Suppression ◽  
Blast Disease ◽  
Rrna Gene ◽  
Isolation And Identification ◽  
Microbiological Methods

Phyllosphere—the harsh foliar plant part exposed to vagaries of environmental and climatic variables is a unique habitat for microbial communities. In the present work, we profiled the phyllosphere microbiome of the rice plants using 16S rRNA gene amplicon sequencing (hereafter termed metabarcoding) and the conventional microbiological methods (culturomics) to decipher the microbiome assemblage, composition, and their functions such as antibiosis and defense induction against rice blast disease. The blast susceptible rice genotype (PRR78) harbored far more diverse bacterial species (294 species) than the resistant genotype (Pusa1602) that showed 193 species. Our metabarcoding of bacterial communities in phyllomicrobiome revealed the predominance of the phylum, Proteobacteria, and its members Pantoea, Enterobacter, Pseudomonas, and Erwinia on the phyllosphere of both rice genotypes. The microbiological culturomic validation of metabarcoding-taxonomic annotation further confirmed the prevalence of 31 bacterial isolates representing 11 genera and 16 species with the maximum abundance of Pantoea. The phyllomicrobiome-associated bacterial members displayed antifungal activity on rice blast fungus, Magnaporthe oryzae, by volatile and non-volatile metabolites. Upon phyllobacterization of rice cultivar PB1, the bacterial species such as Enterobacter sacchari, Microbacterium testaceum, Pantoea ananatis, Pantoea dispersa, Pantoea vagans, Pseudomonas oryzihabitans, Rhizobium sp., and Sphingomonas sp. elicited a defense response and contributed to the suppression of blast disease. qRT-PCR-based gene expression analysis indicated over expression of defense-associated genes such as OsCEBiP, OsCERK1, and phytohormone-associated genes such as OsPAD4, OsEDS1, OsPR1.1, OsNPR1, OsPDF2.2, and OsFMO in phyllobacterized rice seedlings. The phyllosphere bacterial species showing blast suppressive activity on rice were found non-plant pathogenic in tobacco infiltration assay. Our comparative microbiome interrogation of the rice phyllosphere culminated in the isolation and identification of agriculturally significant bacterial communities for blast disease management in rice farming through phyllomicrobiome engineering in the future.

scholarly journals First Report of Leaf Blight Caused by Pantoea agglomerans on Rice in Korea

Plant Disease ◽  
2010 ◽  
Vol 94 (11) ◽  
pp. 1372-1372 ◽  
Author(s):  
H. B. Lee ◽  
J. P. Hong ◽  
S. B. Kim
Keyword(s):  
16S Rrna ◽  
Natural Infection ◽  
Leaf Blight ◽  
Pantoea Agglomerans ◽  
Tween 20 ◽  
Rrna Gene ◽  
Rice Seedlings ◽  
Isolation And Identification ◽  
First Report ◽  
Stalk Rot

In September 2009, leaf blights were observed on rice (Oryza sativa L., variety Dongjin 1 and Hopyeong) in paddy fields located in Gwangyang and Naju, Jeonnam Province, Korea. Lesions appeared first as water-soaked stripes or light brown-to-slightly reddish spots on the upper blades of the leaves, ultimately causing leaf blight and stalk rot. Ten strains of bacteria were isolated from the blighted leaf samples and four isolates (EML-ORY1, -ORY2, -ORY3, and -ORY4) suspected to be Pantoea spp. were selected on the basis of colony types and sampling sites. The isolates readily grew at 27 to 32°C but growth was significantly lower at 35°C. Using the API 20E system, EML-ORY1, 2, and 3 showed the same reaction patterns and gave 15 positive reactions whereas EML-ORY4 gave 11 positive reactions, but results were negative for arginine dihydrolase, citrate utilization, sorbitol fermentation, and rhamnose fermentation. All strains were considerably different from Pantoea agglomerans ATCC27155, which produced nine positive reactions. The strains were identified based on the 16S rRNA gene sequence analyses. A neighbor-joining tree was generated for the four isolates using PHYLIP with the following known bacterial strains: P. agglomerans DSM3493; P. vagans LMG24199; P. eucalypti LMG24197; P. ananatis ATCC19321; and Kluyvera georgiana ATCC51603. The four isolates from rice formed a monophyletic cluster and were most closely related to P. agglomerans DSM3493 (GenBank AJ2334231) with an average 16S rRNA sequence similarity of 99.0%. GenBank Accession numbers for the four isolates are: EML-ORY1, HM854282; -ORY2, HM854283; -ORY3, HM854284; and -ORY4, HM854285. On the basis of molecular phylogenetic analyses and API 20E test, we determined that the causal pathogen might be a subspecies of P. agglomerans. Pathogenicity tests were performed on 2-week-old rice seedlings (variety Hopyeong) in duplicate with bacterial suspensions containing 1.5 × 109 CFU/ml with 0.001% Tween 20. Of the isolates, EML-ORY3 demonstrated the strongest pathogenicity to rice seedlings when evaluated by five scoring systems on the basis of symptom development and severity levels. Disease symptoms appeared 3 days after artificial inoculation. Symptoms on the inoculated leaves were similar to those of natural infection and included water-soaked stems with a light brown color, blighted leaves, and stalk rot, with no symptoms found on water-treated controls. P. agglomerans, formerly called Enterobacter agglomerans (or Erwinia herbicola), is a group of gram-negative bacteria that belong to the family Enterobacteriaceae (3). Pantoea spp. are known to cause different diseases on a broad range of host plants including gypsophila, cotton, pineapple, maize, barley, onion, melons, and eucalyptus and also have been implicated as opportunistic pathogens in humans (1,2). P. agglomerans has been widely found in nature on leaves, fruits, and the seeds of many crops and is a known endophyte (1,2). To our knowledge, this is the first report of rice leaf blight caused by a putative subspecies of P. agglomerans in Korea. The importance of this pathogen to rice production in Korea is unknown. References: (1) Y. Feng et al. J. Appl. Microbiol. 100:938, 2006. (2) S. Manulis and I. Barash. Mol. Plant Pathol. 4:307, 2003. (3) M. P. Starr. The genus Erwinia. Page 1260 in: The Prokaryotes: A Handbook on Habitats, Isolation and Identification of Bacteria. Springer-Verlag, NewYork, 1981.

DIVERSITY OF CULTURABLE BACTERIAL MICROBIOTA OF THE Eisenia foetida DIGESTIVE TRACT

2018 ◽  
Vol 41 (3) ◽  
pp. 255-264 ◽  
Author(s):  
J. Abraham Pérez-Pérez ◽  
David Espinosa-Victoria ◽  
Hilda V. Silva-Rojas ◽  
Lucía López-Reyes
Keyword(s):  
Bacterial Diversity ◽  
Digestive Tract ◽  
Bacterial Species ◽  
Brain Heart Infusion ◽  
Rrna Gene ◽  
Eisenia Foetida ◽  
Bacterial Isolates ◽  
Bacterial Microbiota ◽  
Decomposition Of Organic Matter ◽  
Earthworm Gut

Bacteria are an unavoidable component of the natural earthworm diet; thus, bacterial diversity in the earthworm gut is directly linked to decomposition of organic matter and development of the surrounding plants. The aim of this research was to isolate and to identify biochemically and molecularly the culturable bacterial microbiota of the digestive tract of Eisenia foetida. Earthworms were sourced from Instituto de Reconversión Productiva y Bioenergética (IRBIO) and Colegio de Postgraduados (COLPOS), México. Bacterial isolation was carried out on plates of Brain Heart Infusion (BHI) culture medium. Fifty six and 44 bacterial isolates were obtained from IRBIO and COLPOS, respectively. The population was composed of 44 Gram-negative and 56 Gram-positive isolates. Over 50 % of the bacterial isolates were rod-shaped cells. The 16S rRNA gene was sequenced and nine genera were identified in worms from IRBIO (Bacillus, Paenibacillus, Solibacillus, Staphylococcus, Arthrobacter, Pantoea, Stenotrophomonas, Acinetobacter and Aeromonas) and six in worms from COLPOS (Bacillus, Paenibacillus, Stenotrophomonas, Staphylococcus, Acinetobacter and Aeromonas). Bacillus was the predominant genus, with eight and six species in the oligochaetes from IRBIO and COLPOS, respectively. The most represented bacteria in the worms from both sites were Bacillus sp. and B. subtilis. The predominance of Bacillus was probably due to spore formation, a reproductive strategy that ensures survival and dispersion in the soil and oligochaetes digestive tract. The gut of E. foetida not only harbored bacterial species of agronomic importance but also species potentially pathogenic for humans (Staphylococcus warneri, Pantoea agglomerans and Stentrophomonas sp.). The larger bacterial diversity in worms from IRBIO could be due to their feeding on cattle manure, which is a rich source of bacteria.

Screening and Molecular Characterization of Cellulase Producing Actinobacteria from Litchi Orchard

2019 ◽  
Vol 13 (1) ◽  
pp. 90-101
Author(s):  
Sanju Kumari ◽  
Utkarshini Sharma ◽  
Rohit Krishna ◽  
Kanak Sinha ◽  
Santosh Kumar
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Molecular Characterization ◽  
Biochemical Characterization ◽  
Evolutionary Relationship ◽  
Gene Sequencing ◽  
Cellulase Activity ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Rrna Gene Sequencing

Background: Cellulolysis is of considerable economic importance in laundry detergents, textile and pulp and paper industries and in fermentation of biomass into biofuels. Objective: The aim was to screen cellulase producing actinobacteria from the fruit orchard because of its requirement in several chemical reactions. Methods: Strains of actinobacteria were isolated on Sabouraud’s agar medium. Similarities in cultural and biochemical characterization by growing the strains on ISP medium and dissimilarities among them perpetuated to recognise nine groups of actinobacteria. Cellulase activity was measured by the diameter of clear zone around colonies on CMC agar and the amount of reducing sugar liberated from carboxymethyl cellulose in the supernatant of the CMC broth. Further, 16S rRNA gene sequencing and molecular characterization were placed before NCBI for obtaining recognition with accession numbers. Results: Prominent clear zones on spraying Congo Red were found around the cultures of strains of three groups SK703, SK706, SK708 on CMC agar plates. The enzyme assay for carboxymethylcellulase displayed extra cellulase activity in broth: 0.14, 0.82 and 0.66 &#181;mol mL-1 min-1, respectively at optimum conditions of 35°C, pH 7.3 and 96 h of incubation. However, the specific cellulase activities per 1 mg of protein did not differ that way. It was 1.55, 1.71 and 1.83 μmol mL-1 min-1. The growing mycelia possessed short compact chains of 10-20 conidia on aerial branches. These morphological and biochemical characteristics, followed by their verification by Bergey’s Manual, categorically allowed the strains to be placed under actinobacteria. Further, 16S rRNA gene sequencing, molecular characterization and their evolutionary relationship through phylogenetics also confirmed the putative cellulase producing isolates of SK706 and SK708 subgroups to be the strains of Streptomyces. These strains on getting NCBI recognition were christened as Streptomyces glaucescens strain SK91L (KF527284) and Streptomyces rochei strain SK78L (KF515951), respectively. Conclusion: Conclusive evidence on the basis of different parameters established the presence of cellulase producing actinobacteria in the litchi orchard which can convert cellulose into fermentable sugar.

Molecular Detection of Bacterial Pathogens Directly from the Nasal Swabs and Lung Tissue of Sheep and Goats

2019 ◽  
Vol 15 (02) ◽  
pp. 22-25
Author(s):  
Sunaina Thakur ◽  
Subhash Verma ◽  
Prasenjit Dhar ◽  
Mandeep Sharma
Keyword(s):  
Pasteurella Multocida ◽  
Direct Detection ◽  
Bacterial Species ◽  
Economic Losses ◽  
Isolation And Identification ◽  
Sheep And Goats ◽  
Histophilus Somni ◽  
Nasal Swabs ◽  
Mycoplasma Spp

Respiratory infections of sheep and goats cause heavy morbidity and mortality, leading to huge economic losses. Conventional methods of diagnosis that include isolation and identification of incriminating microbes are time-consuming and fraught with logistic challenges. Direct detection of incriminating microbes using molecular tools is gaining popularity in clinical, microbiological settings. In this study, a total of 50 samples (44 nasal swabs and 6 lung tissues) from sheep and goats were screened for the detection of different bacterial species by in vitro amplification of genus or species-specific genes. Histophilus somni was detected in 2% goat samples, Trueperella pyogenes in 20% goat nasal swabs, whereas 22% goat nasal swab samples were found positive for Mycoplasma spp. None of the samples from sheep was detected positive for H. somni, T. pyogenes, Mycoplasma spp. Similarly, all samples, irrespective, whether from sheep or goats, showed negative results for Pasteurella multocida, Mannheimia haemolytica, and Corynebacterium pseudotuberculosis.

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