Correction: Ibrahimi et al. Marine Actinobacteria: Screening for Predation Leads to the Discovery of Potential New Drugs against Multidrug-Resistant Bacteria. Antibiotics 2020, 9, 91

In the original publication, there was a mistake in Figure 1b as published [...].

The potential of facultative predatory Actinomycetota spp. and prospects in agricultural sustainability

Actinomycetota in the phylum of bacteria has been explored extensively as a source of antibiotics and secondary metabolites. In addition to acting as plant growth-promoting agents, they also possess the potential to control various plant pathogens; however, there are limited studies that report the facultative predatory ability of Actinomycetota spp. Furthermore, the mechanisms that underline predation are poorly understood. We assessed the diversity of strategies employed by predatory bacteria to attack and subsequently induce the cell lysing of their prey. We revisited the diversity and abundance of secondary metabolite molecules linked to the different predation strategies by bacteria species. We analyzed the pros and cons of the distinctive predation mechanisms and explored their potential for the development of new biocontrol agents. The facultative predatory behaviors diverge from group attack "wolfpack," cell-to-cell proximity "epibiotic," periplasmic penetration, and endobiotic invasion to degrade host-cellular content. The epibiotic represents the dominant facultative mode of predation, irrespective of the habitat origins. The wolfpack is the second-used approach among the Actinomycetota harboring predatory traits. The secondary molecules as chemical weapons engaged in the respective attacks were reviewed. We finally explored the use of predatory Actinomycetota as a new cost-effective and sustainable biocontrol agent against plant pathogens.

Antibiotic resistance patterns of carbapenemase-producing Enterobacterales in Mohammed VI University Hospital of Marrakech, Morocco

OBJECTIVES

The emergence and spread of Carbapenem-Resistant Enterobacterales (CRE) has become a growing concern for health services, internationally, nationally, and regionally. In Morocco, the situation is more worrisome as studies on CRE are scarce and/or scattered and/or outdated. As a result, we carried out the present study to determine and update CRE prevalence at Mohammed VI University Hospital of Marrakech, Morocco.

PATIENTS AND METHODS

A cross-sectional prospective study was carried out from March 2018 to March 2020 on 41161 clinical specimens of 23,469 patients suspected of bacterial infections. Enterobacterales strains were isolated following standard bacteriological procedures. Bacterial strains were identified using BD-Phoenix and MALDI-TOF-MS. Antibiotic susceptibility was determined for 14 antibiotics. Carbapenemase production and phenotypic detection were characterized using modified carbapenem inactivation phenotypic and immunochromatographic methods.

RESULTS

All in all, 484 Enterobaterales resistant to at least one carbapenem were recovered. The majority was isolated from the neonatal unit (14%), followed by the urology-nephrology (11%), and plastic surgery departments (10%). K. pneumoniae (n=232) was the most isolated, followed by E. cloacae (n=148), E. coli (n=56), and S. marcescens (n=17). Antibiotic susceptibility profile showed high rates of resistance to ciprofloxacin (75.21%), gentamicin (84.50%), and cotrimoxazole (88.42%). Out of 484 CRE positive cultures, 388 (80.16%) were Carbapenemase-positive. Out of the latter, 170 were metallo-beta-lactamase producers (NDM), 162 OXA-48-like, and 56 both.

CONCLUSION

These findings emphasize the urgent need for control precautions and strict measures to contain and mitigate this issue.

Global potential distribution of three underappreciated arboviruses vectors (Aedes japonicus, Aedes vexans and Aedes vittatus) under current and future climate conditions

Arboviruses (arthropod-borne viruses) are expanding their geographic range, posing significant health threats to millions of people worldwide. This expansion is associated with efficient and suitable vector availability. Apart from the well-known Aedes aegypti and Ae. albopictus, other Aedes species may potentially promote the geographic spread of arboviruses because these viruses have similar vector requirements. Aedes japonicus, Ae. vexans and Ae. vittatus are a growing concern, given their potential and known vector competence for several arboviruses including dengue, chikungunya, and Zika viruses. In the present study, we developed detailed maps of their global potential distributions under both current and future (2050) climate conditions, using an ecological niche modeling approach (Maxent). Under present-day conditions, Ae. japonicus and Ae. vexans have suitable areas in the northeastern United States, across Europe and in southeastern China, whereas the tropical regions of South America, Africa and Asia are more suitable for Ae. vittatus. Future scenarios anticipated range changes for the three species, with each expected to expand into new areas that are currently not suitable. By 2050, Ae. japonicus will have a broader potential distribution across much of Europe, the United States, western Russia and central Asia. Aedes vexans may be able to expand its range, especially in Libya, Egypt and southern Australia. For Ae. vittatus, future projections indicated areas at risk in sub-Saharan Africa and the Middle East. As such, these species deserve as much attention as Ae. aegypti and Ae. albopictus when processing arboviruses risk assessments and our findings may help to better understand the potential distribution of each species.

Assessment of actinobacteria use in the elimination of multidrug-resistant bacteria of Ibn Tofail hospital wastewater (Marrakesh, Morocco): a chemometric data analysis approach

The efficiency of the treatment of hospital wastewater by actinobacteria was investigated using two chemometric data analysis methods. Six strains of multi-resistant bacteria isolated from Marrakesh hospital wastewater and four strains of antagonistic actinobacteria isolated from Moroccan marine environment were characterized by fatty acids released as methyl esters by thermochemolysis-GC/MS. The hierarchical cluster analysis (HCA) and the principal component analysis (PCA) were used to correlate fatty acids (FA) distributions within strains. HCA allowed to discriminate between bacteria and actinobacteria. A lower Euclidean distance is noted for bacteria. With PCA, linear and branched-chained FAs correlated with bacteria whereas mono unsaturated FAs correlated more specifically with Gram (-) bacteria. Terminally branched-chained FAs correlated most likely with actinobacteria. A co-culture of actinobacteria and bacteria monitored during 15 days demonstrated the efficiency of the biological treatment for 2 of the 4 studied actinobacteria. The effect is more important on Gram-negative bacteria. Antagonistic actinobacteria seem to be poorly efficient against Gram-positive bacteria.

Dissemination of Carbapenemases (OXA-48, NDM and VIM) Producing Enterobacteriaceae Isolated from the Mohamed VI University Hospital in Marrakech, Morocco

The emergence and spread of carbapenem-resistant Enterobacteriaceae (CRE) represent a major clinical problem and raise serious health concerns. The present study aimed to investigate and ascertain the occurrence of CRE among hospitalized patients of Mohamed VI University Hospital, Marrakech, Morocco. Biological samples were collected over a one-year period (2018). The bacterial isolates were identified by MALDI-TOF-MS. Antibiotic susceptibility testing was performed using disc diffusion and Etest. The modified Hodge test and combined disc diffusion test were used for phenotypic detection. CRE hydrolyzing enzyme encoding genes: blaOXA-48, blaKPC, blaIMP, blaVIM, and blaNDM were characterized by PCR and DNA sequencing. In total, 131 non-duplicate CRE clinical strains resistant to Ertapenem were isolated out of 1603 initial Enterobacteriaceae. Klebsiella pneumoniae was the most common species (59%), followed by Enterobacter cloacae (24%), E. coli (10%), Citrobacter freundii (3%), Klebsiellaoxycota (2%), Serratia marcescens (1%), and Citrobacter braakii (1%). Of these, 56.49%, 21.37%, 15.27%, 3.38%, and 3.05% were collected from blood, urine, pus, catheters and respiratory samples, respectively. Approximately 85.5% (112/131) of the isolates were carbapenemase producers (40 blaOXA-48, 27 blaNDM, 38 blaOXA-48 + blaNDM and 7 blaVIM). All metallo-β-lactamases isolates were NDM-1 and VIM-1 producers. This is the first documentation of blaOXA-48 genes from C. freundii and C. braakii in Morocco.

Rift Valley Fever and West Nile virus vectors in Morocco: Current situation and future anticipated scenarios

Rift Valley Fever (RVF) and West Nile virus (WNV) are two important emerging Arboviruses transmitted by Aedes and Culex mosquitoes, typically Ae. caspius, Ae. detritus and Cx. pipiens in temperate regions. In Morocco, several outbreaks of WNV (1996, 2003 and 2010), affecting horses mostly, have been reported in north-western regions resulting in the death of 55 horses and one person cumulatively. Serological evidence of WNV local circulation, performed one year after the latest outbreak, revealed WNV neutralizing bodies in 59 out of 499 tested participants (El Rhaffouli et al., 2012). The country also shares common borders with northern Mauritania, where RVF is often documented. Human movement, livestock trade, climate changes and the availability of susceptible mosquito vectors are expected to increase the spread of these diseases in the country. Thus, in this study, we gathered a data set summarizing occurrences of Ae. caspius, Ae. detritus and Cx. pipiens in the country, and generated model prediction for their potential distribution under both current and future (2050) climate conditions, as a proxy to identify regions at-risk of RVF and WNV probable expansion. We found that the north-western regions (where the population is most concentrated), specifically along the Atlantic coastline, are highly suitable for Ae. caspius, Ae. detritus and Cx. pipiens, under present-day conditions. Future model scenarios anticipated possible range changes for the three mosquitoes under all climatic assumptions. All of the studied species are prospected to gain new areas that are currently not suitable, even under the most optimist scenario, thus placing additional human populations at risk. Our maps and predictions offer an opportunity to strategically target surveillance and control programmes. Public health officials, entomological surveillance and control delegation must augment efforts and continuously monitor these areas to reduce and minimize human infection risk.

Impact of carbonatation lime addition on composting of vegetable oil refining sludge

The aim of the present work is to evaluate how the vegetable oil refining sludge produced by the agro-food industry could be composted using carbonatation lime and green waste as bulking agents. To achieve this goal, three windrows were prepared with different mixtures: windrow 1 contained oil sludge and green waste (20:10 on a wet mass basis) while windrow 2 contained oil sludge, green waste and carbonatation lime (20:10:10, on a wet mass basis). The composition of windrow 3 was: oil sludge, green waste and carbonatation lime (20:10:20, on a wet mass basis). The results showed that the use of carbonatation lime for composting vegetable oil refining sludge was able to regulate the high acidity of the sludge and thus to obtain an optimal pH value for the launching and maintenance of the composting process. The addition of carbonatation lime also gave better reduction of microbial activity without any negative effect on composting. The compost prepared with oil refining sludge (49% fresh mass), carbonatation lime (27%) and green waste (24%) exhibited the best quality with C/N ratio and pH values within the norm NFU44-051. These promising results could be a sustainable solution for the valorization of both oil refining sludge and sugar carbonatation lime.

Streptomyces thinghirensis sp. nov., isolated from rhizosphere soil of Vitis vinifera

A novel actinomycete, strain S10(T), was isolated from rhizosphere soil of wild Vitis vinifera in Thinghir, Ouarzazate Province, Southern Morocco. The taxonomic status of this strain was established using a polyphasic approach. Strain S10(T) had white-grey aerial mycelium with long, spiral spore chains bearing smooth surfaced spores and produced a yellow diffusible pigment. Chemotaxonomic analyses showed that the cell wall of strain S10(T) contained ll-diaminopimelic acid and glycine. Phylogenetic analysis based on the almost complete 16S rRNA gene sequence indicated that strain S10(T) belonged to the Group I streptomycetes, branching off next to Streptomyces marokkonensis LMG 23016(T) from the Streptomyces violaceoruber group. DNA-DNA relatedness and phenotypic data distinguished strain S10(T) from the phylogenetically closest related type strains. It is therefore proposed that strain S10(T) (=CCMM B35(T)=DSM 41919(T)) represents the type strain of a novel species of the genus Streptomyces, for which the name Streptomyces thinghirensis sp. nov. is proposed.