title: Characterization and antimicrobial activities of two Streptomyces isolates from soil in the periphery of Universiti Putra Malaysia.
abstract: This study was to assess the identification and antimicrobial activities of two   actinomycete isolates. The two isolates designated as B8 and C2, were isolated from a patch   of soil in the peripheral area of Universiti Putra Malaysia by streaking on starch casein agar   after standard serial dilution procedures. Their antimicrobial activities were first evaluated   against eight clinical laboratory strains namely Bacillus sp., Enterococcus sp., Escherichia   coli, Klebsiella sp., Pseudomonas sp., Salmonella sp., Staphylococcus aureus, and   Staphylococcus epidermidis by perpendicular streak method on Mueller Hinton and Tryptic   Soy agar. In both media, a broad-spectrum antibacterial activity was observed for both   isolates, with B8 against all the test bacteria and C2 against five of them (Bacillus sp., E. coli,   Pseudomonas sp., S. aureus and S. epidermidis). Re-assessment against E. coli ATCC 25922   and S. aureus ATCC 25923 strains by similar method showed antibacterial activities by   isolate B8 against both ATTC strains while C2 only against S. aureus ATCC 25923. Streptomyces   griseus ATCC 10137 was included in the later experiment and showed antibacterial activity   against both ATCC strains. Subsequently, the two isolates were identified by PCR/sequencing   techniques and phylogenetic analysis to be Streptomyces species (>93% homology based on   16S rRNA and rpoB genes). Characterization on cultural characteristic and viable count at   different temperatures (37ºC and 28ºC), on different microbiological media (AIA, ISP-2, MHA,   NA, PDA and TSA), were performed. More morphological features were observed on ISP-2 for   both isolates. A higher growth yield was also observed at 28ºC in all media but in comparing   that between the two isolates, isolate B8 outnumbered C2 at all experimental conditions. The   observed variation in cultural traits and growth yield indicate unique properties between the   two antibiotic-producing isolates.
authors.affiliation: Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors.forename: Nurul Zarith Mohamad
authors.initials: NZ
authors.lastname: Zin
authors.forename: Nor Asmara
authors.initials: NA
authors.lastname: Tasrip
authors.forename: Mohd Nasir Mohd
authors.initials: MN
authors.lastname: Desa
authors.forename: Cheah Yoke
authors.initials: CY
authors.lastname: Kqueen
authors.forename: Zainul Amiruddin
authors.initials: ZA
authors.lastname: Zakaria
authors.forename: Rukman Awang
authors.initials: RA
authors.lastname: Hamat
authors.forename: Mariana Nor
authors.initials: MN
authors.lastname: Shamsudin
mesh_terms: D000046:Academic Medical Centers; D000900:Anti-Bacterial Agents / Q000378:metabolism*; D000898:Antibiosis; D001431:Bacteriological Techniques; D016000:Cluster Analysis; D003470:Culture Media / Q000737:chemistry; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D006801:Humans; D008296:Malaysia; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D013302:Streptomyces / Q000145:classification* / Q000302:isolation & purification / Q000502:physiology*; D013696:Temperature
chemical_list: D000900:Anti-Bacterial Agents; D003470:Culture Media; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S