Swarming and Swimming Movement of Bacteria in Different Organic Wastes
Trends Journal of Sciences Research, Volume 4, Issue 1, 2019, Pages 14–20.
Received November 16, 2018; Revised December 31, 2018; Accepted January 08, 2019; Published January 09, 2019
Motility plays an important role in biofilm formation and movement in different environmental conditions, colonization, and adhesion of bacteria to surfaces. The lowest swimming was 3 (mm) in agar medium and the highest value was 42.67 (mm) with the addition of WCW. The lowest swarming was carried out in agar medium with 7.66 (mm), while the highest value was found in N.A medium with the addition of 10% WCW 59.33 (mm). In all experimental conditions, an increase of 2.4 times (swimming) and 6.4 times (swarming) was observed after the addition of WCW to the controls.
Bacterial growth and movement plays an important role in many different areas such as soil microbiology, water treatment and microbial pathogenesis 1.
Swarming is a social phenomenon that involves rapid coordinated movement of bacteria across a semisolid surface. The swarming requires the production of a functional flagellum and rhamnolipid surfactant. The sliding motion is separate from the swimming motion because swimming is the movement required to move on an aqueous, viscous semi-solid surface while allowing movement in a liquid medium of relatively low viscosity 2, 3, 4, 5, 6, 7, 8, 9, 10.
Swarming colonies of different bacterial genera share several common dynamic characteristics: the alignment of adjacent cells and their coordinated movement in multicellular rafts; the low curvature of their trajectories; the low frequency of cell tumbles; the formation of dynamic, circular vortices of cells; and the cooperative motility of cells across surfaces 11, 12.
Swarming motility has been reported in a wide range of Gram (-) bacterial species belonging to the genera Proteus, Vibrio, Aeromonas, Serratia, Bacillus, Salmonella, Escherichia, Yersinia, and Pseudomonas. Pseudomonas aeruginosa has the potential to move on viscous surfaces by swarming motility 2, 3, 4, 6, 9, 13, 14.
Swimming in the aquatic environment and in low agar concentrations (0.3% agar) to flagellum; IV type pilus on solid surfaces mediated swarming and recently observed swimming over semi-solid (viscous) medium (0.5 to 0.7% agar). Swimming is generally defined as a dendritic-like colonial appearance and a social phenomenon that typically involves coordinated and rapid movement of bacteria along a semi-solid surface 10, 16, 17, 18, 19.
The swimming and movement of the bacteria along the surfaces using various mechanisms in aqueous environments is seen in many different forms. Swimming along a surface occurs when the liquid film is sufficiently thick and the morphological structure of the bacteria is not fully organized. When a surface liquid layer is examined or when cells are inoculated to the surface of the agar medium, vegetative cells begin a differentiation process as multinucleated cells and prolonged, hyper flagellated cells 20.
Swimming motility provides a significant advantage for bacteria by allowing them to move away from toxins and alien species towards suitable conditions 21.
P. aeruginosa floats with a single, polar, monotric flagellum rotating with proton motivating power. In the context of the disease, this flagellar swimming motility is important in infection because the lack of swimming ability of P. aeruginosa mutant causes a decrease in pathogenesis 22, 23.
Escherichia coli are a rod-shaped Gram (-) bacterium commonly found in the large intestine of warm-blooded animals 12. It is a model organism for the behavior of bacterial cell movement in mechanical and mass fluids 11. In particular, E. coli was used as a prototypic micro-swimmer. E. coli cells close motility is important in the early stages of biofilm formation and pathogenic infection 24. E. coli cells have several extracellular helical thread-like structures called flagella 24, 25.
Bacillus cereus is Gram (+), spore-forming, mobile, aerobic, rod-shaped and anaerobic bacteria. Bacillus subtilis is a soil bacterium that has a versatile metabolism and ability to survive in various habitats. It is known to enter the fusion motility as a cellular differentiation program in nutritional research when exposed to nutritional stress conditions 26, 27. Swarming migration has a bacterial action that can contribute significantly to the pathogenesis of Bacillus infection. Bacteria can be varied into prolonged, multi-core, hyper-flagellated swarmer cells that can move away from the colony in a coordinated manner along a moist, solid surface or in a viscous environment 28.
Staphylococcus aureus is anaerobic; Gram (-) has a coke structure and causes widespread infections 29. It has been shown that S. aureus colonies can be passively propagated along the surface of the soft agar plates with the aid of the production of surfactant in a process called propagation 30.
Enterococcus is a genus of Gram (+) bacteria naturally found in the mammalian gastrointestinal tract. Enterococci are opportunistic pathogens with tolerance to various environmental conditions including extremes of temperature and pH, high salinity, detergents, and anti-biotics 31. However, the characteristics of such ocular E. faecalis strains remain unknown 32.
2. Materials and Methods
P. aeruginosa (ATCC 27853), E. coli (ATCC 25922), S. aureus (ATCC BAA 1026) and B. cereus (ATCC 10876) obtained from the ATCC and used this study.
2.2. Waste cheese whey
Waste cheese whey (WCW) was collected from commercial cheese factories in Malatya, Turkey.
2.3. Waste frying oil
Waste frying oil (WFO) was obtained and collected from the food Restaurant Malatya, Turkey.
2.4. Sugar beet molasses
Sugar beet molasses (SBM) was collected from Malatya Sugar Factories in Malatya, Turkey. These wastes were filtered for removing crude impurities and then, they’re autoclaved, and then used.
2.5. Growth conditions
Bacteria were firstly cultured in Luria- Bertani (LB) broth medium (g l-1); peptone (10), NaCl (10), and yeast extract (5). The final pH values of broth media was adjusted to 7.0. The same amounts of cells were grown at 37 °C, 0 rpm on incubator for overnight (O/N). 100 μl of over night cultures (OD600 nm ~ 0,2-0,3) grown tube filled with 5 ml in 10 ml tubes was inoculated, and incubated for 24 h of time. Phosphate-buffered saline (PBS buffer) (gl-1: 8,0 NaCl; 0,2 KCl; 1,44 Na2HPO4; 0,24 KH2PO4 and pH 7,4) and PBS+10 % wastes. These cultures were subsequently incubated on an orbital shaker at 0, 100 rpm, 200 rpm and 37 °C for 24 h.
Swimming and swarming assays was determined using modified methods with WCW as the substrate. Swimming. Swimming plates were composed of 0.3% Nutrient Agar, supplemented with 10% wastes and sterile phosphate-buffered saline supplemented with 10% WCW. Swarming. Swarm plates were composed of 0.5% Bacto Agar and 8 g/L of nutrient broth, supplemented with 10% wastes and sterile phosphate-buffered saline supplemented with 10% wastes petri dishes. Petri dishes, dried overnight at room temperature. Cells were point inoculated with a sterile pipette 6 μl, and the plates were incubated at 25 and for 24 hours, respectively. Motility was then assessed qualitatively by examining the circular turbid zone formed by the bacterial cells migrating away from the point of inoculation 3, 9, 13, 17, 18, 23, 33. Each value is the average of three independent experiments.
3.1. Agar Media Swarming
In the presence of melas in S. aureus with the highest swarming 21.66 mm, the lowest swarming motion was in the presence of WFO in E. faecalis. The biggest difference was observed in the presence of S. aureus and molasses with 17.33 mm. No movement was observed since there was no breeding of B. cereus in the presence of molasses. When WFO was added, there was no growth in E. faecalis and therefore no swarming motions were detected. The highest percentage difference was observed in E. faecalis with % 500 differences in the molasses environment (Figure 1, Figure 2, Figure 3, Figure 4).
3.2. Nutrient Agar Media Swarming
The highest swarming 59,33 mm with P. aeruginosa in WCW, while the lowest sliding motion was observed in E. faecalis with the presence of molasses 7 mm. The largest difference was observed in P. aeruginosa and WCW with 35 mm. The largest difference was observed in P. aeruginosa and WCW with 35 mm. The lowest difference was observed in the presence of molasses in E. faecalis with 0,7 mm. According to the control group in the presence of molasses, only P. aeruginosa decline. The highest rate of different was observed in 271 % B. cereus and WFO environment, while the lowest difference in molasses was observed in E. faecalis (111%). When all the results were taken into consideration, the sliding motion was more observed in the presence of molasses in agar medium; it was observed in the presence of WCW in the NA environment (Figure 1, Figure 2, Figure 3, Figure 4).
All bacteria were able to slip in the NA environment, while B. cereus and E. faecalis could not perform in agar medium.
3.3. Agar Media Swimming
In the presence of melas in P. aeruginosa with the highest swimming 19.33 mm in WCW, the lowest swimming motion (3 mm) was in the presence of WFO in B. cereus. The biggest difference was observed in the presence of P. aeruginosa and WCW with 16.33 mm. No movement was observed since there was no breeding of B. cereus and E. faecalis in the presence of molasses. When WFO was added, there was no growth in P. aeruginosa and E. faecalis and therefore no swimming motions were detected. The highest percentage difference was observed in P. aeruginosa with % 644 difference in the WCW environment. The lowest percentage difference was observed in P. aeruginosa with % 111 difference in the molasses environment (Figure 1, Figure 2, Figure 3, Figure 4).
3.4. Nutrient Agar Media Swimming
The highest swimming 55 mm with S. aureus in molasses, while the lowest swimming motion observed in E. faecalis with the presence of molasses 4.33 mm. The largest difference was observed in S. aureus and molasses with 47.33 mm. The lowest difference was observed with E. faecalis and 1.1 mm in molasses. According to the control group in the presence of molasses swimming is decline. The highest rate of different was observed in 717 % S. aureus and molasses environment, while the lowest difference in molasses was observed in E. faecalis (115%) (Figure 1, Figure 2, Figure 3, Figure 4).
When all the results were taken into consideration, the swimming motion was more observed in the presence of WCW in agar medium; it was observed in the presence of WCW in the N.A environment. Considering the Nutrient Agar medium, only B. cereus did not move.