Advanced Journal of Microbiology Research

Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (4), pp. 001-007, April, 2019. © International Scholars Journals

Full Length Research Paper

Characterization of pathogenic or non-pathogenic Enterococcus faecalis isolated from lambs from Xinjiang, a remove North-west province of China

ZHOU Xia*, WANG Dong and WANG Xiao-lan

College of Animal Science and Technology, Xinjiang Shihezi University, Shihezi, 832003, China.

Accepted 23 March, 2019

Abstract

The majority of the 11 pathogenic Enterococcus faecalis from lambs developed encephalitis and 45 non-pathogenic E. faecalis from intestinal and respiratory microbiota of healthy lambs were belonged to Streptococcus serotype D. Haemolytic study revealed that 8 of 11 pathogenic stains had stable haemolyticus; 8/30 strains of intestinal normal microbita and 3 of 15 strains from respiratory system showed unstable haemolyticus. Of 11 pathogenics E. faecalis, 8 of 9 virulence factor genes were detected in all the strains; 5 of 11 expressed Esp, CylA, Asa1, Ace, efa, EF0591 and EF3314 simultaneously and 1 of 11 expressed GelE; Two of 11 did not express any of the 9 virulence factor genes. Among 30 strains isolated from the intestinal microbita, only one had 2 (GelE, EF3314) and one had 3 (GelE, EF3314 and Asa1) of the 9 virulence factor genes. The homology of these 3 common virulence gene fragments (GelE, EF3314 and Asa1) was more than 95% between E. faecalis from GenBank and intestinal microbita and 96% when comparing the E. faecalis isolated from intestinal microbita and from those of pathogenic strains. Antibiotic sensitivity study indicated that all of the 11 pathogenic strains were resistance to a variety of antibiotics in various degrees. In comparison, Only 2 strains from normal flora were resistance to individual antibiotics. In vivo challenge study showed that all of the 11 the pathogenic strains could lead to the death of mice, whereas none of the isolates from normal flora could cause the death of the experimental animals.

Key words: Biochemical characteristic, Enterococcus faecalis, lamb,virulence factor gene.

Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (4), pp. 001-006, April, 2019. © International Scholars Journals

Full Length Research Paper

Molecular characteristic of Staphylococcus aureus isolates in a Chinese teaching hospital

Xiao-Ling Ma¹, Fei-Hu Chen²*, Xin Zhou¹, Wen-Jiao Chang¹ and Yuan-Yuan Dai¹

¹Department of Clinical Laboratory, Anhui Provincial Hospital, Hefei 230001, China.

²School of Pharmacy, Anhui Medical University, Hefei 230032, China.

Accepted 23 Marh, 2019

Abstract

The aim of this study is to investigate the genetic backgrounds of methicillin susceptible Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA) and heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) isolates isolated from clinical specimens of the patients with verified infections in a Chinese teaching hospital. Macro E test (MET) was used to detect hVISA and multilocus sequence typing (MLST) was used to determine the STs of the selected isolates. The genotypes of SCCmec were determined by multiplex polymerase chain reaction (PCR) in MRSA isolates. Panton-valentine leucocidin (PVL) genes were also detected by PCR. Among 273 S. aureus isolates, hospital-acquired methicillin-resistant Staphylococcus aureus (HA-MRSA), community-associated methicillin-resistant S. aureus (CA-MRSA), hospital-acquired methicillin susceptible Staphylococcus aureus (HA-MSSA) and community-associated methicillin susceptible Staphylococcus aureus (CA-MSSA) isolates accounted for 55.6, 1.5, 36.3, and 6.6%, respectively. Nine isolates were confirmed as hVISA by MET. Among 60 HA-MRSA isolates, ST239-MRSA-III was the most prevalent clone accounting for 51.7%, followed by ST5-MRSA-II clone. Fifty percentage and 22.2% of CA-MSSA isolates were found to be ST121 and ST88. ST239-MRSA-III was the predominant clone in hVISA isolates. However, no predominant ST type was found in HA-MSSA isolates. Of 9 PVL-positive strains, ST88 was the most prevalent ST (50.0%; 4/8), followed by ST121 (33.3%; 3/9), ST5 (4.5%; 1/22) and ST239 (2.6%; 1/39). In conclusion, ST239- III was the major pandemic clone in hVISA and HA-MRSA and spread in China. ST5- emerging rapidly in China had remained stable viability.

Key words: Staphylococcus aureus, heterogeneous vancomycin-intermediate Staphylococcus aureus, molecular characteristic.

Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (4), pp. 001-006, April, 2019. © International Scholars Journals

Full Length Research Paper

Cloning and expression of Corynebacterium diphtheriae toxin gene

N. Mohammadi¹, M. Bandehpour ^2,3, P. Pakzad¹ and B. Kazemi^2,3*

¹Islamic Azad University, Tehran North branch, Iran.

²Cellular and Molecular Biology Research Center, Shaheed Beheshti University of Medical Sciences, Tehran, Iran.

³Biotechnology Department, Faculty of Medicine, Shaheed Beheshti University of Medical Sciences, Tehran, Iran.

Accepted 23 March, 2019

Abstract

Diphtheria is an acute bacterial disease caused by oxygenic strains of Corynebacteria. Fatality rate of this disease, between 5 and 10%. In children under 5 years and adults, the fatality rate may be as much as 20%. Outbreaks, although very rare, still occur worldwide, even in developed nations. Diphtheria toxin (DT) is the major virulence factor for these organisms. The aim of this study was cloning and expression diphtheria toxin gene to produce recombinant protein and application in next investigations. The bacterial DNA was extracted and amplification of diphtheria toxin gene was carried out with specific primers. This gene was cloned in pTZ57R/T vector and sub cloned into pETDuet-1 expression vector then recombinant plasmid was transformed into BL21 of Escherichia coli strain and induced by IPTG. Diphtheria toxin gene was amplified successfully and cloned in pTZ57R. Recombinant plasmid was digested by restriction enzymes and released fragment (diphtheria toxin gene) sub cloned in pETDuet-1 expression vector and expressed protein was analysed in serological assay. In this study, the diphtheria toxin gene was cloned in pETDuet-1 expression vector and confirmed by sequencing and restriction analysis then recombinant plasmid was transformed in BL21 expression cell.

Key words: Diphteria, Corynebacterium diphtheriae toxin gene, recombinant protein, pETDuet-1.

Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (4), pp. 001-004, April, 2019. © International Scholars Journals

Full Length Research Paper

IN VIVO and IN VITRO protein profiling in ACACIA NILOTICA (L.): A nitrogen fixing tree

Kshipra  Dhabhai* and Amla Batra

Plant Tissue Culture Laboratory, Department of Botany, University of Rajasthan, Jaipur, Rajasthan 302012, India.

Accepted 22 March, 2019

Abstract

Present investigation was the first attempt which deals with the IN VIVO and IN VITRO comparative study of protein level in ACACIA NILOTICA L., a nitrogen fixing tree. Protein was investigated in callus, seed, leaf and stem by means of SDS-PAGE. For obtaining the IN VITRO explant, the seeds were cultured on ½ MS medium under the IN VITRO condition. The cotyledonary nodal explants were taken from the IN VITRO seedlings and cultured in the MS medium supplemented in combination of 2, 4-D (0.4 mg/l) with BAP (0.25 mg/l). Though some differences were observed in the protein contents of IN VIVO and IN VITRO samples, the data proved that protein content in callus was higher than the seed following leaf and stem. In this study it was found that A. NILOTICA contained several protein bands of molecular weight 54.3, 44.1, 42.7, 40.1, 35.6, 31.2, 28.6, 24.7 and 19.5 kDa. These results indicate that the intensity of protein bands was high in IN VITRO sample compared to IN VIVO samples.

Key words: SDS-PAGE, in vitro, in vivo

Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (4), pp. 001-004, April, 2019. © International Scholars Journals

Full Length Research Paper

Treatment guidelines and nosocomial infections: The South African experience

Essack, S. Y.¹ and Connolly, C.²

¹School of Pharmacy and Pharmacology, University of Kwazulu-Natal, Private Bag X54001, Durban, 4000, South Africa.

²Biostatistics Unit, Medical Research Council, P. O. Box 70380, Overport, 4067, South Africa.

Accepted 22 January, 2019

Abstract

Nationally-devised standard treatment guidelines (STGs) for nosocomial infections were evaluated in the context of antibiotic resistance within the public health care system in Kwazulu-Natal. A multi-centre surveillance study instituted in 3 hospitals at 3 progressive levels of health care (district, regional and tertiary) collected consecutive, non-repetitive isolates commonly implicated in nosocomial infections as cited by the STGs, viz., Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter spp. Isolates were subjected to susceptibility testing against antibiotics recommended in the treatment guidelines as empirical treatment for nosocomial infections using the Kirby Bauer disc diffusion method advocated by the CLSI. Percentage susceptibility across (1) bacterial species, (2) antibiotics and (3) hospital levels was compared. Susceptibility to antibiotics recommended in the treatment guidelines and hence potentially successful empiric therapy ranged from 5 to 95% with multi-resistance evident in all isolates. Statistically significant differences in overall susceptibility were observed (1) across bacterial species, (2) within 2 of the 3 bacterial species for different antibiotics and; (3) across hospital levels for 2 antibiotics with p values <0.001 for across bacterial species, (1), ranging from 0.003 to <0.001 for within 2 of the 3 bacterial species for different antibiotics (2) and ranging from 0.001 to <0.001 for across hospital levels for 2 antibiotics (3). This study showed that the success of empiric therapy as dictated by treatment guidelines would vary depending upon the bacterial species, the antibiotic used and the hospital, thus making a strong case for institution-specific guidelines based on evidence from well-executed surveillance.

Key words: Treatment guidelines, nosocomial infections, antibiotic resistance.

Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (4), pp. 001-011, April, 2019. © International Scholars Journals

Full Length Research Paper

Seasonal variation in the diversity and abundance of phytoplankton in a small African tropical reservoir

ADON Marie Paulette*, OUATTARA Allassane and GOURENE Germain

Université d’Abobo - Adjamé, UFR Sciences et Gestion de l’Environnement, Laboratoire d’Environnement et de Biologie Aquatique, 02 BP 801 Abidjan 02, Côte d’Ivoire.

Accepted 23 February, 2019

Abstract

Phytoplankton species composition and seasonal changes were investigated in the shallow reservoir of Adzopé. Taxonomic composition, diversity and abundance of phytoplankton were studied at 4 stations from May 2008 to February 2009, in relation to physical and chemical factors (temperature, conductivity, dissolved oxygen, transparency, pH, nutrients) and climatic factor (rainfall). The phytoplankton comprised 144 taxa, mainly Chlorophyta (29.45% of taxa), Euglenophyta (29.45%) Bacillariophyta (23.97%) and Cyanobacteria (10.27%). Phytoplankton density values were greatest during the transition season (short rainy season), lower during the dry seasons, and extremely lower during the long rainy season (mean value 356 10⁵ cells/l, 44 10⁵ cells/l and 35 10⁵ cells/l respectively). Abundance was dominated by Anabaena constricta Szafer (Geitler) and Microcystis aeruginosa (Kütz.) Kütz. The diversity index varied between 2.1 bits/cells in long rainy season and 4.6 bits/cells in short dry season. The redundancy analysis (RDA) demonstrated a separation between the long rainy season and the other seasons due to the influence of the flood pulse.

Key words: Phytoplankton, shallow reservoir, species dominance, West Africa.