title: Composition of soil microbiome along elevation gradients in southwestern highlands of Saudi Arabia.
abstract: BACKGROUND
  Saudi Arabia is mostly barren except the southwestern highlands that are susceptible to environmental changes, a hotspot for biodiversity, but poorly studied for microbial diversity and composition. In this study, 454-pyrosequencing of 16S rRNA gene hypervariable region V6 was used to analyze soil bacterial community along elevation gradients of the southwestern highlands.
  
  
  RESULTS
  In general, lower percentage of total soil organic matter (SOM) and nitrogen were detected in the analyzed soil samples. Total 33 different phyla were identified across the samples, including dominant phyla Proteobacteria, Actinobacteria and Acidobacteria. Representative OTUs were grouped into 329 and 508 different taxa at family and genus level taxonomic classification, respectively. The identified OTUs unique to each sample were very low irrespective of the altitude. Jackknifed principal coordinates analysis (PCoA) revealed, overall differences in the bacterial community were more related to the quantity of specific OTUs than to their diversity among the studied samples.
  
  
  CONCLUSIONS
  Bacterial diversity and soil physicochemical properties did not show consistent changes along the elevation gradients. The large number of OTUs shared between the studied samples suggest the presence of a core soil bacterial community in the southwestern highlands of Saudi Arabia.
authors.affiliation: Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia. yasirkhattak.mrl@gmail.com.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Yasir
authors.affiliation: Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia. eazhar@kau.edu.sa.|Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia. eazhar@kau.edu.sa.
authors.forename: Esam I
authors.initials: EI
authors.lastname: Azhar
authors.affiliation: Biochemistry Department, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia. rustamkhan31@yahoo.com.
authors.forename: Imran
authors.initials: I
authors.lastname: Khan
authors.affiliation: Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia. fehmeedaimran@yahoo.com.
authors.forename: Fehmida
authors.initials: F
authors.lastname: Bibi
authors.affiliation: Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia. rnda.m.b@hotmail.com.
authors.forename: Rnda
authors.initials: R
authors.lastname: Baabdullah
authors.affiliation: Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia. iaalzahrani1@kau.edu.sa.
authors.forename: Ibrahim A
authors.initials: IA
authors.lastname: Al-Zahrani
authors.affiliation: Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia. aalghamdi@kau.edu.sa.
authors.forename: Ahmed K
authors.initials: AK
authors.lastname: Al-Ghamdi
mesh_terms: D000531:Altitude; D001419:Bacteria / Q000145:classification* / Q000235:genetics*; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D054892:Metagenome; D064307:Microbiota; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012529:Saudi Arabia; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S