Not really. The horizontal gene transfer pool is local - you'll find microsystems where the plasmid or gene segment is present, but unless the gene itself provi

Not really. The horizontal gene transfer pool is local - you'll find microsystems where the plasmid or gene segment is present, but unless the gene itself provides some fitness benefit to the host, it will be outcompeted in general. You'd expect a tiny reservoir of the gene to remain in circulation in heavily plastic polluted areas with low nutrient density, but you wouldn't expect the gene to represent a gain of function phenotypic change to the general microbe population. When these hybrids are initially created, they'd likely be created via transfected plasmids that produce a ton of the enzyme - the fitness downside for a bacteria to produce a non-mutated version of the plasmid would be phenomenally large. In the same way that we can create little insulin factory bacteria, our little plastic enzyme bacteria are not going to turn the world into grey goo; they're literally parasitized and weaker than wildtype at existing in the wild. If they weren't, they'd be the wildtype.