Heavy metal pollution generally occurs due to socio-economic, industrial, and anthropogenic activities, which may cause an environmentally hazardous and serious severe threat to the survival of the organisms (genotoxic, carcinogenic, and clastogenic effects on it). Many physical and chemical remediation approaches have been proposed to deal with this pollution, but these are very time-consuming and costly. While bioremediation stands out as an inexpensive and efficient approach, the use of bacteria is thought to be a potential and productive organism to prevent this pollution. This review has evaluated the bacterial potential to clean up heavy metals from the environment and elucidated the mechanisms responsible for bioremediation.

Önümüzdeki yüzyılda küresel iklimin büyük ölçüde değişeceği ve ekosistemlerin bu değişen ortamdan etkileneceği tahmin ediliyor. Bitki ile ilişkili faydalı mikroorganizmalar, bitki büyümesini uyarabilir ve biyotik ve abiyotik streslere karşı direnci artırabilir. Günümüzde artan karbondioksit (CO2), kuraklık ve ısınma gibi iklim değişikliği faktörlerinin bitki faydalı mikroorganizma etkileşimleri üzerindeki etkileri, bitki gelişimi ve sağlığı kapsamında giderek daha fazla araştırılmaktadır. Son çalışmalar, yüksek CO2 seviyesinin mikorizal fungusların bolluğu üzerinde olumlu bir etkiye sahip olduğunu, buna karşın bitki büyümesini teşvik eden bakteriler ve endofitik mantarlar üzerindeki etkilerinin daha değişken olduğunu göstermiştir. Ek olarak, artan CO2 seviyeleri, ısınma ve kuraklığın sonuçları bitkiye ve mikrobiyal genotipe bağlıdır. Ayrıca bitki büyümesini teşvik eden mikroorganizmalar, özellikle bakteriler, kuraklık stresine maruz kalan bitkileri olumlu yönde etkiler. İklim değişikliklerine bağlı olarak değişen faydalı mikroorganizma toplulukları, farklı mikrobiyal topluluklarla rekabet etmek zorunda kalabilir ve bu nedenle mikrobiyal faaliyetler de etkilenebilir. Bu çalışma, iklim değişikliğinin mikroorganizma ve bitki etkileşimlerini etkileyen önemli bir faktör olduğunu, bitkilerde ve mikroorganizmalarda adaptasyon süreçlerinin dikkate alınması gerektiğini ve adapte edilmiş bitki çeşitlerinin seçimini gerektirebileceğini ortaya koymaktadır.

Global climate is estimated to change drastically over the next century and the ecosystems will be affected in this changing environment. Plant-associated beneficial microorganisms can stimulate plant growth and increase resistance to biotic and abiotic stresses. Nowadays, the effects of climate change factors such as increased carbon dioxide (CO2), drought and warming on plant-beneficial microorganism interactions are increasingly being investigated in the scope of plant growth and health. Recent studies have shown that high CO2 level has a positive effect on the abundance of mycorrhizal fungi, whereas the effects on plant growth promoting bacteria and endophytic fungi are more variable. Elevated CO2 conditions lead to increased colonization of beneficial fungi. Additionally, the results of increasing CO2 levels, warming and drought, depend upon the plant and the microbial genotype. Also, plant growth promoting microorganisms, especially bacteria, positively affect plants exposed to drought stress. Altered communities of beneficial microorganisms depending on climate changes, might have to compete with different microbial communities and, therefore microbial activities may also get affected. This work presents that climate change is an important factor affecting microorganism and plant interactions, needs to take into consideration the adaptation processes in plants and microorganisms and might require the selection of adapted plant cultivars.

Bacterial pathogens are isolated, identified and antibiogram were performed by taking the skin, gills and intestine of twenty randomly selected Tilapia fish (Oreochromis niloticus) that collected from local market of the Dinajpur city, Bangladesh. A serial dilution was prepared with the stated sample and at the amount of 0.1 ml was plated on nutrient agar, differential also specific media respectively. Then gram’s staining, colony morphology, biochemical test and antibiogram performed respectively. The four different isolated species with frequency of occurrence are 31(40.26%) Escherichia coli, 3 (29.87%) Staphylococcus spp., 13 (16.88%) Pseudomonas spp., 10 (12.99%) Salmonella spp. respectively. Some of these pathogens have tendency to transmit to man, who eat fish or deal with fish and fish products. Amoxicillin, Cefixime, Azithromycin, Chloramphenicol, Ciprofloxacin, Penicillin G, Erythromycin, Vancomycin, Gentamicin and Neomycin antibiotics was performed during sensitivity test. Among the total (77) isolated bacteria were sensitive to gentamycin, chloramphenicol, ciprofloxacin and Azithromycin but resistant to Amoxicillin, Penicillin G, Vancomycin and Erythromycin. The study was conducted in term of medical importance. Hence it is considered that a variety of bacterial species can be associated with fresh Tilapia fish related pathogen to humans.