American Journal of Microbiological Research

ISSN (Print): 2328-4129

ISSN (Online): 2328-4137


Current Issue» Volume 3, Number 3 (2015)


Molecular Study of Panton-Valentine Leukocidin Genes among Staphylococcus aureus Clinical Isolates in Khartoum State, Sudan

1Department of Biotechnology, Faculty of Science and Technology, Omdurman Islamic University, Sudan

2College of Applied Medical Science, Shaqra University, KSA

3Department of Microbiology, Tropical Medicine Research Institute, National Center for Research, Sudan

4Department of Microbiology, Faculty of Medicine, King Khalid University, KSA

5Department of Biotechnology, Biotechnology Park, Africa City of Technology, Sudan

American Journal of Microbiological Research. 2015, 3(3), 107-111
DOI: 10.12691/ajmr-3-3-2
Copyright © 2015 Science and Education Publishing

Cite this paper:
Najem Aldin M. Osman, Intisar E. Alrayah, Yassir Mahgoub Mohamed, Ali M El-Eragi, Muataz M. Eldirdery, Mohamed Ahmed Salih. Molecular Study of Panton-Valentine Leukocidin Genes among Staphylococcus aureus Clinical Isolates in Khartoum State, Sudan. American Journal of Microbiological Research. 2015; 3(3):107-111. doi: 10.12691/ajmr-3-3-2.

Correspondence to: Najem  Aldin M. Osman, Department of Biotechnology, Faculty of Science and Technology, Omdurman Islamic University, Sudan. Email:


Staphylococcus aureus strains carrying Panton- Valentine Leukocidin genes (PVL) are an emerging threat worldwide, causing variety of infections even in healthy individuals. Intensive efforts through the last years have been carried out towards the detection and analysis of PVL genes. The prevalence and characterization of such genes has not been done in Sudan. In this study we investigated the prevalence and the molecular characteristics of PVL genes among S. aureus clinical isolates, comparing their PVL allelic variant with that of PVL positive strains from different countries. Standard microbiological procedures were used for the identification of isolates, polymerase chain reaction for determination of PVL genes and standard sequencing for mapping of lukS/F-PV genes. In Silico tools were used for sequence analysis. Among 210 S. aureus isolates, PVL genes were detected in 122 (58%). Sequence analysis for lukS/F-PV genes from 12 representative isolates detected a new point mutation in lukS PV region. Collectively, our findings showed a high frequency of PVL genes among S. aureus isolates and revealed a novel nonsynonymous mutation. Phylogenetic analysis revealed that Sudanese isolates were closely related to each other.



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Removal of Heavy Metals from Aqueous Solutions Using Multi-Metals and Antibiotics Resistant Bacterium Isolated from the Red Sea, Egypt

1Botany Department, Faculty of Science, Menoufia University, Egypt

2Marine Microbiology Laboratory, National Institute of Oceanography and Fisheries, Egypt

3Marine Pollution Laboratory, National Institute of Oceanography and Fisheries, Egypt

American Journal of Microbiological Research. 2015, 3(3), 93-106
DOI: 10.12691/ajmr-3-3-1
Copyright © 2015 Science and Education Publishing

Cite this paper:
Mohamed T. Shaaban, Hassan A.H. Ibrahim, Ahmed S. Abouhend, Khalid M. El-Moselhy. Removal of Heavy Metals from Aqueous Solutions Using Multi-Metals and Antibiotics Resistant Bacterium Isolated from the Red Sea, Egypt. American Journal of Microbiological Research. 2015; 3(3):93-106. doi: 10.12691/ajmr-3-3-1.

Correspondence to: Ahmed  S. Abouhend, Marine Pollution Laboratory, National Institute of Oceanography and Fisheries, Egypt. Email:,


This investigation was incorporate screening for the highest multiple metal and antibiotics resistant marine bacteria at the Northern Red Sea. The two selected bacterial isolates were identified on the basis of phenotypic and genotypic characterization through 16S rDNA gene technique as Alteromonas macleodii and Nitratireductor basaltis. A. macleodii revealed high efficiency in the removal of heavy metals from aqueous solution. Different factors influenced the removal of heavy metals from aqueous solution by A. macleodii such salinity, pH, temperature, biomass and contact time were optimized. The metal removal was greater at the lowest initial metal concentration (50 mg l-1) and decreased with increase in the metal concentration. A. macleodii showed high efficiency in biosorption of different metals in single and multiple metal solution systems. Removal percentage of different metals by A. macleadii in a single metal system at the highest tested metal concentrations (200 mg l-1) reached Pb, 73.8%; Mn, 66%; Fe, 65%; Cu, 64%; Zn, 62%; Ni, 54%; and Cd, 53%. In multiple metal systems containing 30 mg l-1 of different metals, biosorption percentage was Pb, 93%; Fe, 89%; Zn, 55%; Cd, 50%; Cu, 44.5%; Mn, 40% and Ni, 36%. These findings suggest the possibility of using these bacterial isolates for bioremediation of heavy metals from heavy metal contaminated ecosystem.



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