In line with the high rubber consumption, efficient rubber
disposal and recycling methods must be practically applied. The
hydrophobic and resilient property of rubber cause a problem in
rubber composting, thus the recycling of rubber is an alternative to
manage the solid waste of rubber. The methods of recycling rubber
products are based on two concepts which are, the product reuse
and the material reuse. However, the existing methods of disposal
and recycling of rubber products are difficult and less environmental
friendly [3,4]. Other than rubber waste management, the
waste generated from the rubber producing industries must also be
taken into consideration. Environmental problems associated with
the processes in rubber production have been reported [5].
It is important to develop a more efficient and environmental
friendly method for the rubber disposal and the waste generated
from rubber industry in order to deal with the environmental
problems addressed. Studies have shown that natural rubber can be
degraded by some microorganisms [6e9]. The substrates that can
be degraded and mineralized by these rubber-degrading microorganisms
are not only limited to natural rubber, even vulcanized
rubber (chemically cross-linked rubber) can be the substrates of
biodegradation [10e12]. These studies have shown that the rubberdegrading
microorganisms could provide a biotechnological solution
to the problem of waste rubbers. These microorganisms have
been divided into two groups, which are the clear zone formers and
the non-clear zone formers. Clear zone formers are able to grow
and produce clearing zones on latex overlay agar. The second group
of rubber-degrading microorganisms do not produce clearing zones
on latex overlay agar. Instead, they grow adhesively on rubber
substrates [13,14].
To date, the molecular mechanism of rubber biodegradation is
not fully understood. Thus far, only two key enzymes named rubber
oxygenase A (RoxA) and latex clearing protein (Lcp) responsible for
rubber degradation have been reported [15,16]. More enzymes
associated with the rubber degradation are yet to be identified in
order to understand its mechanism. In this study, we successfully
identified one rubber-degrading bacterial strain and two potential
rubber-degrading bacterial strains from aged latex based on the lcphomologous
sequences from their genomes. Among these, two
bacterial strains were postulated as new potential rubberdegrading
bacteria