A study on an oligotrophic bacteria and its ecological characteristics in an arid desert area

Abstract

An oligotrophic bacterium was isolated from the biological soil crust underlayer in the Xinjiang Gurbantunggut Desert. It was numbered SGB-5, G + . Cell size is (0.328-0.746) µm×(0.171-0.240) µm. Raised colony is white, roundness and its diameter is 5 mm. The strain is a facultative aerobe. It was able to grow in conditions of 1-15 mg·C·L −1 culture medium at 10-50℃. The strain's optimum growth temperature is 37℃. The range of its optimum growth pH is 8-9. A large amount of extracellular mucopolysaccharide was secreted during growth. The chemical composition of this mucopolysaccharide consists of arabinose, X sugar, glucose, galactose and mannitol. Mole ratio of these sugars is 1 : 14 : 19 : 6 : 14. The viscosity of the mucopolysaccharide can reach 6300 mPa·s, when the strain is cultivated for 72 h. After the culture solution in which viscosity was 1500 mPa·s was sprinkled on the quicksand surface, 6 mm bacteria crust of conglutinating sand was formed. This crust could not only stabilize sand, but could also potentially slow the rate of the soil water evaporation.

Microbial Extracellular Polymeric Substances: Ecological Function and Impact on Soil Aggregation

“…An unidentified bacterium isolated from biological soil crusts (BSCs) from the Gurbantünggüt Desert stabilized sand surface, producing aggregation and slowing the soil water evaporation after only 8 days of inoculation. In addition, the EPS of the bacterium produced the conglutination of sand particles, as observed by scanning electron microscopy ( HuiXia et al, 2007 ). Another isolate from Gurbantünggüt Desert, Paenibacillus KLBB0001 – a strong EPS producer – was inoculated in the desertic soil to improve the recovery of BSCs.…”

Controlling rainfall-induced soil loss from small experimental plots through inoculation of bacteria and cyanobacteria

“…The characteristics of identified bacteria and cyanobacteria have been summarized in Supplementary Tables 1 and 2. Based on desired characteristics explained before, the Azotobacter and Bacillus subtilis strain from bacteria and also Nostoc, Oscillatoria and Lyngbya from cyanobacteria were selected as the most appropriate microorganisms to be applied for targeting the study goals. In this regard, Huixia et al (2007) introduced Oligotrophic bacteria including Bacillus as suitable bacteria for soil characteristics improvement in deserts. Maqubela et al (2009) reported that the soil aggregate and carbon sequestration increased after Nostoc inoculation on corn field soil.…”

Response of microorganisms and enzymes to soil contamination with a mixture of pethoxamid terbuthylazine

“…The response of oligotrophic bacteria different from other groups of microorganisms may result from different abilities of microorganisms to degrade plant protection products and from oligotrophic bacteria being microorganisms with low nutritional requirements. In addition, they have a membrane which constitutes a barrier against harmful environmental factors (HuiXia et al 2007). An increase in the count of oligotrophic bacteria in soil supplemented with pethoxamid and terbuthylazine (the active substances of the herbicide Successor T 550 SE) was also observed in the previous studies by our team, conducted under strictly controlled conditions (Tomkiel et al 2014).…”