Pub Date : 2019-02-26DOI: 10.15406/jmen.2019.07.00241
Z. Aminzadeh, Atefeh Sadat Akhavi Mirab, M. Goudarzi, N. Zahed
Infections due to Staphylococcus aureus account for a major cause of morbidity and mortality in hemodialysis patients.1,2 Colonization of S.aureus is associated with a four-fold higher risk of bloodstream infection. Hemodialysis patients suffer from a high rate of infection or colonization with MRSA which lead to increased rate of mortality, length of hospital stay, and healthcare costs compared to those infected with methicillin-susceptible S. aureus.3,4 Methicillin susceptible S.aureus changes to MRSA by acquisition of staphylococcal Cassette Chromosome mec (SCCmec) a genomic island that encodes methicillin resistance.5 The tst gene, a mobile genetic element, encodes Toxic shock syndrome toxin 1 (TSST-1) a superantigenic toxin secreted by both MRSA and MSSA.6 Besides, Panton-Valentine leukocidin is a gamma-toxin mostly produced by CA-MRSA.7 The aim was to determine the presence of mecA, lukS/lukF-PV (PVL), eta & etb genes (exfoliative toxin A & B) and tst genes (TSST-1) in two S.aureus colonized patients.
{"title":"Nasal colonization of SCCmec II, III and tst-1 positive Methiticillin resistance Staphylococcal aureus isolated from patients in a hemodialysis unit, Tehran, Iran","authors":"Z. Aminzadeh, Atefeh Sadat Akhavi Mirab, M. Goudarzi, N. Zahed","doi":"10.15406/jmen.2019.07.00241","DOIUrl":"https://doi.org/10.15406/jmen.2019.07.00241","url":null,"abstract":"Infections due to Staphylococcus aureus account for a major cause of morbidity and mortality in hemodialysis patients.1,2 Colonization of S.aureus is associated with a four-fold higher risk of bloodstream infection. Hemodialysis patients suffer from a high rate of infection or colonization with MRSA which lead to increased rate of mortality, length of hospital stay, and healthcare costs compared to those infected with methicillin-susceptible S. aureus.3,4 Methicillin susceptible S.aureus changes to MRSA by acquisition of staphylococcal Cassette Chromosome mec (SCCmec) a genomic island that encodes methicillin resistance.5 The tst gene, a mobile genetic element, encodes Toxic shock syndrome toxin 1 (TSST-1) a superantigenic toxin secreted by both MRSA and MSSA.6 Besides, Panton-Valentine leukocidin is a gamma-toxin mostly produced by CA-MRSA.7 The aim was to determine the presence of mecA, lukS/lukF-PV (PVL), eta & etb genes (exfoliative toxin A & B) and tst genes (TSST-1) in two S.aureus colonized patients.","PeriodicalId":91326,"journal":{"name":"Journal of microbiology & experimentation","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42884023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-02-07DOI: 10.15406/jmen.2019.07.00240
Nusrat Perween, H. Khan, Nazish Fatima
In comparison to bacterial pathogens, fungi were less frequently the cause of infectious diseases in humans earlier. However, with the increased number of immunosuppressed patients, fungal infections have gained enormous medical importance. And, today Candida spp. have become common nosocomial pathogens and even serious systemic Candida infections may frequently lead to death and represents a serious public health challenge with increasing medical and economic importance due to the high mortality rates and increased costs of care and duration of hospitalization.1,2 Intensive use of antifungal drugs has led to an incessant increase in the number of resistant fungal strains retaining viability due to their resistance mechanisms.3 Initially sensitive Candida spp. were shown to acquire resistance to various antifungal agents, after gradual exposure to increasing concentrations of these agents. This development of resistance was found to be due to mutation.4 Pfaller et al.,5 reported that exposure of C.glabrata to subtherapeutic concentration of fluconazole may result in resistance.
{"title":"Silver nanoparticles: an upcoming therapeutic agent for the resistant Candida infections","authors":"Nusrat Perween, H. Khan, Nazish Fatima","doi":"10.15406/jmen.2019.07.00240","DOIUrl":"https://doi.org/10.15406/jmen.2019.07.00240","url":null,"abstract":"In comparison to bacterial pathogens, fungi were less frequently the cause of infectious diseases in humans earlier. However, with the increased number of immunosuppressed patients, fungal infections have gained enormous medical importance. And, today Candida spp. have become common nosocomial pathogens and even serious systemic Candida infections may frequently lead to death and represents a serious public health challenge with increasing medical and economic importance due to the high mortality rates and increased costs of care and duration of hospitalization.1,2 Intensive use of antifungal drugs has led to an incessant increase in the number of resistant fungal strains retaining viability due to their resistance mechanisms.3 Initially sensitive Candida spp. were shown to acquire resistance to various antifungal agents, after gradual exposure to increasing concentrations of these agents. This development of resistance was found to be due to mutation.4 Pfaller et al.,5 reported that exposure of C.glabrata to subtherapeutic concentration of fluconazole may result in resistance.","PeriodicalId":91326,"journal":{"name":"Journal of microbiology & experimentation","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45824781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-02-06DOI: 10.15406/jmen.2019.07.00239
Mario Galindo-M
Objectives: To investigate putative reservoirs of CTX-M extended spectrum β-lactamase- producing Enterobacteriaceae (ESBL-E) in Oaxaca, Mexico. Methods: Samples from different putative reservoirs of these organisms were analyzed and included human and dog feces, tap water, fresh beef and chicken meat, salsas and vegetables from street vendors and domestic flies in household kitchens and restaurants. Identification of ESBL-E was performed according to CLSI guidelines; molecular characterization of bla CTX-M strains was performed using PCR. Results: Except for tap water, all the analyzed niches act as reservoir of ESBL-E clones in our community. The prevalence of either ESBL-E contamination or colonization varies depending on the reservoir under study, from very high (78/104) in human fecal carriage to non-existent (0/30) in tap water; 96.2% (150/156) of the ESBL-E positive clones harbored the bla CTX-M gene. Conclusions: Contamination or fecal colonization of ESBL-E clones in our community is largely spread and our results suggest that, if overuse of antibiotics plays a key role in the appearance of antibacterial resistance clones, the lack of hygiene measures may play a pivotal role in the spread of ESBL-E to humans.
{"title":"Reservoirs of CTX-M extended spectrum β-lactamase-producing Enterobacteriaceae in Oaxaca, Mexico","authors":"Mario Galindo-M","doi":"10.15406/jmen.2019.07.00239","DOIUrl":"https://doi.org/10.15406/jmen.2019.07.00239","url":null,"abstract":"Objectives: To investigate putative reservoirs of CTX-M extended spectrum β-lactamase- producing Enterobacteriaceae (ESBL-E) in Oaxaca, Mexico. Methods: Samples from different putative reservoirs of these organisms were analyzed and included human and dog feces, tap water, fresh beef and chicken meat, salsas and vegetables from street vendors and domestic flies in household kitchens and restaurants. Identification of ESBL-E was performed according to CLSI guidelines; molecular characterization of bla CTX-M strains was performed using PCR. Results: Except for tap water, all the analyzed niches act as reservoir of ESBL-E clones in our community. The prevalence of either ESBL-E contamination or colonization varies depending on the reservoir under study, from very high (78/104) in human fecal carriage to non-existent (0/30) in tap water; 96.2% (150/156) of the ESBL-E positive clones harbored the bla CTX-M gene. Conclusions: Contamination or fecal colonization of ESBL-E clones in our community is largely spread and our results suggest that, if overuse of antibiotics plays a key role in the appearance of antibacterial resistance clones, the lack of hygiene measures may play a pivotal role in the spread of ESBL-E to humans.","PeriodicalId":91326,"journal":{"name":"Journal of microbiology & experimentation","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48107252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-01-31DOI: 10.15406/jmen.2019.07.00238
Prasansah Shrestha, N. Pokhrel, A. D. Pant
Patients with ESRD (End-stage renal disease) have a high incidence of bacterial infections.2 This increased susceptibility to bacterial infections is due in part to the acquired immune deficiency state of uremia, advanced age, and comorbid conditions such as diabetes mellitus (DM), as well as the frequent and repetitive exposure of patients to potential infectious risk factors during the normal course of dialysis therapy.3
{"title":"Bacteriology of blood stream infections in diabetic and non diabetic patients under the course of hemodialysis: a mini-review","authors":"Prasansah Shrestha, N. Pokhrel, A. D. Pant","doi":"10.15406/jmen.2019.07.00238","DOIUrl":"https://doi.org/10.15406/jmen.2019.07.00238","url":null,"abstract":"Patients with ESRD (End-stage renal disease) have a high incidence of bacterial infections.2 This increased susceptibility to bacterial infections is due in part to the acquired immune deficiency state of uremia, advanced age, and comorbid conditions such as diabetes mellitus (DM), as well as the frequent and repetitive exposure of patients to potential infectious risk factors during the normal course of dialysis therapy.3","PeriodicalId":91326,"journal":{"name":"Journal of microbiology & experimentation","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45416297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-01-22DOI: 10.15406/jmen.2019.07.00237
Afonso Cardoso, A. Silva, De Almeida Lm, Monteiro Em
According to the World Health Organization (WHO), infections are responsible for 25% of deaths worldwide. In 1990, it was estimated that 16 million people died from infections. In 2010, the number of deaths dropped to 15 million, with a decline of only 1% per year. And for 2050, the WHO predicts that 13 million deaths will be attributed to these causes, even with a number of measures for prevention and prophylaxis are recommended and implemented for these conditions.1 The causative organisms of these infections are increasingly developing resistance mechanisms currently available pharmacological treatment, and multidrug resistant organisms are called (MDR). Microbial resistance is the ability of a microorganism to withstand the action of an antimicrobial agent. This resistance is a major threat to global public health, it increases the morbidity and mortality of the population and impose huge costs on all countries.2 In the United States, infections caused by MDR organisms burden by more than 20 billion dollars a year and generating spending more than $8 million due to additional hospitalizations.3 In the European Union, it is estimated that about 25,000 people may die annually infections caused by bacteria and the associated costs are estimated at about 1.5 billion euros per year.4
{"title":"Insights on antimicrobial stewardship in the microbiology laboratory: a review","authors":"Afonso Cardoso, A. Silva, De Almeida Lm, Monteiro Em","doi":"10.15406/jmen.2019.07.00237","DOIUrl":"https://doi.org/10.15406/jmen.2019.07.00237","url":null,"abstract":"According to the World Health Organization (WHO), infections are responsible for 25% of deaths worldwide. In 1990, it was estimated that 16 million people died from infections. In 2010, the number of deaths dropped to 15 million, with a decline of only 1% per year. And for 2050, the WHO predicts that 13 million deaths will be attributed to these causes, even with a number of measures for prevention and prophylaxis are recommended and implemented for these conditions.1 The causative organisms of these infections are increasingly developing resistance mechanisms currently available pharmacological treatment, and multidrug resistant organisms are called (MDR). Microbial resistance is the ability of a microorganism to withstand the action of an antimicrobial agent. This resistance is a major threat to global public health, it increases the morbidity and mortality of the population and impose huge costs on all countries.2 In the United States, infections caused by MDR organisms burden by more than 20 billion dollars a year and generating spending more than $8 million due to additional hospitalizations.3 In the European Union, it is estimated that about 25,000 people may die annually infections caused by bacteria and the associated costs are estimated at about 1.5 billion euros per year.4","PeriodicalId":91326,"journal":{"name":"Journal of microbiology & experimentation","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45289925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-01-18DOI: 10.15406/jmen.2019.07.00236
X. Ji, Qian Chen, Li Wang, P. Du
Wrightoporiopsis YC Dai, Jia J Chen & BK Cui, typified by W. neotropica (Ryvarden) YC Dai, Jia J Chen & BK Cui, was recently established by Chen et al.1 Some of taxa in the genus were previously treated under Wrightoporia Pouzar.2–4 However, Phylogenetic analysis demonstrated that Wrightoporiopsis is distant from Wrightoporia sensu stricto, and these two genera in fact belong to two families, Hericiaceae and Wrightoporiaceae, respectively.1 Wrightoporiopsis is characterized by pileate, yellow to yellowish-brown basidiocarps, a dimitic hyphal system with generative hyphae bearing clamp connections, skeletal hyphae usually dextrinoid, basidiospores ellipsoid to subglobose, hyaline, finely asperulate, strongly amyloid, and causing a white rot.1
以W. neotropica (Ryvarden)为代表的Wrightoporiopsis, YC Dai, Jia J Chen & BK Cui是最近由Chen等人建立的1 .该属的一些分类群以前被命名为Wrightoporia Pouzar.2-4，但系统发育分析表明，Wrightoporiopsis与Wrightoporia sensu stricto相距较远，这两个属实际上分别属于Hericiaceae和Wrightoporiaceae两个科担孢子的特征是:有毛状、黄色到黄褐色的担子果，二殖体的菌丝系统具有生殖菌丝夹接，骨架菌丝通常为糊精状，担子孢子椭球状到近球形，透明的，细细的asperulate，强烈的淀粉样，并引起白色腐烂
{"title":"A new species of Wrightoporiopsis (Russulales, Basidiomycota) and a key to accepted species in the genus","authors":"X. Ji, Qian Chen, Li Wang, P. Du","doi":"10.15406/jmen.2019.07.00236","DOIUrl":"https://doi.org/10.15406/jmen.2019.07.00236","url":null,"abstract":"Wrightoporiopsis YC Dai, Jia J Chen & BK Cui, typified by W. neotropica (Ryvarden) YC Dai, Jia J Chen & BK Cui, was recently established by Chen et al.1 Some of taxa in the genus were previously treated under Wrightoporia Pouzar.2–4 However, Phylogenetic analysis demonstrated that Wrightoporiopsis is distant from Wrightoporia sensu stricto, and these two genera in fact belong to two families, Hericiaceae and Wrightoporiaceae, respectively.1 Wrightoporiopsis is characterized by pileate, yellow to yellowish-brown basidiocarps, a dimitic hyphal system with generative hyphae bearing clamp connections, skeletal hyphae usually dextrinoid, basidiospores ellipsoid to subglobose, hyaline, finely asperulate, strongly amyloid, and causing a white rot.1","PeriodicalId":91326,"journal":{"name":"Journal of microbiology & experimentation","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67077285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-01-10DOI: 10.15406/jmen.2019.07.00234
X. Ji, R. Du
The genus Skeletocutis Kotl. & Pouzar was established in 1958 and its type species is Skeletocutis amorpha Fr. Kotlába & Pouzar.1 The genus is widely distributed around the world, but the majority of the species known so far are found in the Northern Hemisphere.2‒5 Species in Skeletocutis cause white rot. They mostly have resupinate basidioma although the genus type has pileate or effused-reflexed basidioma. The generative hyphae, at least, partly covered by fine crystals and the tiny basidiospores are the most important characteristics of the genus.3,5 Skeletocutis is phylogenetically close to Tyromyces P. Karst., Ceriporiopsis Domański and Piloporia Niemelä, and they cluster within the Tyromyces clade.6,7 Currently only two species have been described from Southeast Asia, Skeletocutis falsipileata (Corner) T Hatt8 in Malaysia and Skeletocutis bicolor (Lloyd) Ryvarden9 in Singapore. Seven species (Skeletocutis fimbriata Juan Li & YC Dai, S. luteolus BK Cui & YC Dai, S. substellae YC Dai, S. bambusicola LW Zhou & WM, S. inflata BK Cui & YC Dai, S. yunnanensis LS Bian, S. pseudo-odora LF Fan & Jing Si) were described in five provinces in southern China.10‒16 During a survey of lignicolous fungi in Vietnam in October 2017, two specimens were collected growing on angiosperm trunks, and have resupinate basidioma with a distinct cottony sterile margin, relatively small pores, plenty of hyphal pegs, a dimitic hyphal structure, generative hyphae bearing clamp connections and fine, sharp-pointed encrustations especially at the dissepiment edges, bottle-shaped cystidioles and pyriform to ovoid basidiospores. These characters fitted the genus of Skeletocutis, but we could not assign them to a name and so we describe the collections as a new species.
{"title":"A new species of Skeletocutis (Polyporales, Basidiomycota) from Vietnam","authors":"X. Ji, R. Du","doi":"10.15406/jmen.2019.07.00234","DOIUrl":"https://doi.org/10.15406/jmen.2019.07.00234","url":null,"abstract":"The genus Skeletocutis Kotl. & Pouzar was established in 1958 and its type species is Skeletocutis amorpha Fr. Kotlába & Pouzar.1 The genus is widely distributed around the world, but the majority of the species known so far are found in the Northern Hemisphere.2‒5 Species in Skeletocutis cause white rot. They mostly have resupinate basidioma although the genus type has pileate or effused-reflexed basidioma. The generative hyphae, at least, partly covered by fine crystals and the tiny basidiospores are the most important characteristics of the genus.3,5 Skeletocutis is phylogenetically close to Tyromyces P. Karst., Ceriporiopsis Domański and Piloporia Niemelä, and they cluster within the Tyromyces clade.6,7 Currently only two species have been described from Southeast Asia, Skeletocutis falsipileata (Corner) T Hatt8 in Malaysia and Skeletocutis bicolor (Lloyd) Ryvarden9 in Singapore. Seven species (Skeletocutis fimbriata Juan Li & YC Dai, S. luteolus BK Cui & YC Dai, S. substellae YC Dai, S. bambusicola LW Zhou & WM, S. inflata BK Cui & YC Dai, S. yunnanensis LS Bian, S. pseudo-odora LF Fan & Jing Si) were described in five provinces in southern China.10‒16 During a survey of lignicolous fungi in Vietnam in October 2017, two specimens were collected growing on angiosperm trunks, and have resupinate basidioma with a distinct cottony sterile margin, relatively small pores, plenty of hyphal pegs, a dimitic hyphal structure, generative hyphae bearing clamp connections and fine, sharp-pointed encrustations especially at the dissepiment edges, bottle-shaped cystidioles and pyriform to ovoid basidiospores. These characters fitted the genus of Skeletocutis, but we could not assign them to a name and so we describe the collections as a new species.","PeriodicalId":91326,"journal":{"name":"Journal of microbiology & experimentation","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48317356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-01-04DOI: 10.15406/jmen.2019.07.00233
R. Vasudevan
Biofilms are commonly referred to as extra cellular matrices or extra polymeric structures composed of bio molecules and are known for their complexity. They confer the pathogen with a variety of functions that make them resilient and virulent. The current mini review attempts to highlight the significance of agr/sarA regulators and their role as molecular switches in the formation and dispersal of Staphylococcus biofilms.
{"title":"Agr/sarA: Molecular switches of biofilm regulation in Staphylococcus aureus","authors":"R. Vasudevan","doi":"10.15406/jmen.2019.07.00233","DOIUrl":"https://doi.org/10.15406/jmen.2019.07.00233","url":null,"abstract":"Biofilms are commonly referred to as extra cellular matrices or extra polymeric structures composed of bio molecules and are known for their complexity. They confer the pathogen with a variety of functions that make them resilient and virulent. The current mini review attempts to highlight the significance of agr/sarA regulators and their role as molecular switches in the formation and dispersal of Staphylococcus biofilms.","PeriodicalId":91326,"journal":{"name":"Journal of microbiology & experimentation","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48696896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-01-04DOI: 10.15406/jmen.2019.07.00231
J. S. Toledo
In 2002, Ruud Jansen of Utrecht University found a 21-37 bp interspaced short sequence repeats distinctly spaced among several bacterial species, such as, Salmonella typhimurium (21bp) and Streptococcus pyogenes (37bp). Jansen’s team found that CRISPRs were unique to certain prokaryotes and not viruses and eukaryotes. Moreover, they identified a common sequence, GTT/AAC, at the ends and a long homologous sequence along the upstream without an open reading frame, indicating a conserved ncRNA segment. Their findings were similar to that of Ishino and Mojica, and they have referred the phenomenon as Clustered Regularly Interspaced Short Palindormic Repeats (CRISPR). The biological meaning of CRISPR remained obscure until 2005, when Pourcel, Mojica and Bolotin, independently, concluded that CRISPR were clearly derived from extrachromosomal DNA elements, with most being similar to bacteriophage and plasmids. Outstandingly, species containing CRISPR elements were protected against corresponding foreign invaders and had no residual prophage as evidence of prior infections.4‒6
{"title":"Genome editing based on CRISPR/CAS systems: beginning of a new era of genetic manipulation and inheritance","authors":"J. S. Toledo","doi":"10.15406/jmen.2019.07.00231","DOIUrl":"https://doi.org/10.15406/jmen.2019.07.00231","url":null,"abstract":"In 2002, Ruud Jansen of Utrecht University found a 21-37 bp interspaced short sequence repeats distinctly spaced among several bacterial species, such as, Salmonella typhimurium (21bp) and Streptococcus pyogenes (37bp). Jansen’s team found that CRISPRs were unique to certain prokaryotes and not viruses and eukaryotes. Moreover, they identified a common sequence, GTT/AAC, at the ends and a long homologous sequence along the upstream without an open reading frame, indicating a conserved ncRNA segment. Their findings were similar to that of Ishino and Mojica, and they have referred the phenomenon as Clustered Regularly Interspaced Short Palindormic Repeats (CRISPR). The biological meaning of CRISPR remained obscure until 2005, when Pourcel, Mojica and Bolotin, independently, concluded that CRISPR were clearly derived from extrachromosomal DNA elements, with most being similar to bacteriophage and plasmids. Outstandingly, species containing CRISPR elements were protected against corresponding foreign invaders and had no residual prophage as evidence of prior infections.4‒6","PeriodicalId":91326,"journal":{"name":"Journal of microbiology & experimentation","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43166939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-01-04DOI: 10.15406/jmen.2019.07.00230
J. Jamriška, Terézia Lučeničová
The immature stages of a large number of blowflies are parasitized by parasitic wasps with local or cosmopolitan distribution.2‒4 Several species parasitize pupae of bird blowflies by penetrating the host pupae. One such group of parasitic wasps, are solitary or gregarious ectophagous parasitoids from the Pteromalidae family. The most commonly world-wide distributed is Nasonia vitripennis. Its life cycle is well established because it has been widely used in genetic and field studies5,6 and pupal parasitoids have attracted a lot of attention because of their potential control of house and stable flies in farms.1 A female parasite with matured eggs drills through the host pupae with her ovipositor laying eggs externally on the pupa and injects a substance, to narcotize or kill the host. The female feeds on haemolymph from the host tissues. The parasite larvae feed throughout the three instars, and then pupate, and the adult’s enclose approximately 24 hours before biting one or more holes and emerging from the host pupa. The same emergence hole is used by successive emerges, and the males usually emerge before the females.6‒8 The females do not drill pupae which have an emergence hole of a fly or parasites, otherwise it drills without laying eggs if the host is not pupated or is dead or contains late instars parasite larvae or adults.7 Temperature and humidity are important factors in the survival of the wasp, and in unsuitable conditions for further development the third instar can be diapaused. Previously there has been little information about the parasitization of bird blowflies under natural conditions. Eshuis van der Voet9 recorded that 48.8 % of Protocalliphora spp. pupae were infested by this parasitic wasp in Parus major nests in Holland, while in the USA, 20.1 % of these species pupae found to be parasitized by the same wasp.2 The parasitization of N. vitripennis reported by Peters4 was 42.1% in Protocalliphora azurea (cele meno) pupae and 15.8% in Protocalliphora falcozi (cele meno) pupae.
大量飞蝇的未成熟阶段被当地或世界性分布的寄生蜂寄生。2-4几个物种通过穿透寄主蛹寄生在飞蝇的蛹中。其中一类寄生蜂是翅目昆虫科的独居或群居的外食性寄生蜂。世界范围内最常见的分布是玻璃藻。它的生命周期已经确立，因为它已被广泛用于遗传和田间研究5，6，而蛹寄生蜂由于其对农场中的室内和稳定苍蝇的潜在控制而引起了很多关注，麻醉或杀死宿主。雌性以宿主组织的血淋巴为食。寄生虫幼虫在三龄期进食，然后化蛹，成虫在咬一个或多个洞并从寄主蛹中出来之前大约24小时。连续羽化使用相同的羽化孔，雄性通常先于雌性羽化。6-8雌性不会钻出有苍蝇或寄生虫羽化孔的蛹，否则，如果宿主未化蛹或死亡，或含有晚龄寄生虫幼虫或成虫，则会在不产卵的情况下钻出。7温度和湿度是影响黄蜂生存的重要因素，在不适合进一步发育的条件下，三龄幼虫可以滞育。以前很少有关于在自然条件下寄生在鸟类身上的信息。Eshuis van der Voet9记录到，48.8%的原愈伤组织蛹在荷兰的Parus主要巢穴中被这种寄生蜂寄生，而在美国，20.1%的这些物种的蛹被发现被同一种黄蜂寄生。2 Peters报告的N.vanicpennis的寄生率4在天青原愈伤组织（cele meno）蛹中为42.1%，在法尔科兹原愈伤组织中为15.8%。
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